The Food Groupie Club

Hi my name is Sarah and I'm addicted to food. I have been a chef professionally for about 12 years now and am currently teaching cooking classes at a culinary school. I seriously love to cook and eat good food. The problem with cooking and eating like the professionals though is that it can be kind of intimidating for a home food enthusiast. My goal is to bring good food into every-day homes. Anyone can make healthy, good quality, good tasting, and good looking food with the right know-how. So here you made easy by a professional!

I will be featuring some of my favorite chef's recipes in my posts and will note in the post what book was used. Their books that I use will be listed in my must have cookbooks tab.

Saturday, January 5, 2013

Bouchon Cream Puffs (Pate A Choux)

Pages 160-163 Bouchon Bakery Book- Thomas Keller

Guess what was released last year??
Seriously this was the best thing that happened to me in all of 2012. Sad? Maybe. But I don't really think so.  Anyone who has eaten ANYTHING at Bouchon Bakery must get this book.  All his best stuff is in here including the TKO, Better Nutters, Oh Oh's, and an expanded macaroon section.
I decided to kick it a little classic today and talk about Pate A Choux (pronounced like pat a shoe), which is the dough used for cream puffs and eclairs.  So excited this was in the Bouchon book! There's actually a whole section of things you can make with Pate a ChouxThomas Keller of course did a little bit of a twist on a classic and made this crispy "sugar cookie" to go on top of the cream puff that gave it an amazing crunchy texture and made it look a little more rustic. I really liked the combo a lot. Here is a picture of the finished product. How would you not want that to be in your belly?

For the dough:
1 cup + 1 1/2 Tbs Water
4 1/2 ounces Unsalted butter, room temperature
heaping 3/4 tsp. Salt
1 cup AP flour
1 cup whole eggs

For the cookie:
3/4 cup + 3 tbs. Brown sugar
1 cup + 1 Tbs. AP flour
1/4 cup almond meal
3 ounces unsalted butter

Making the Pate A Choux :

Step 1.  Combine water, butter, and salt in medium sauce pan over medium heat.  Let simmer until butter has melted, stirring regularly. Make sure the liquid reaches a boil, turn off the heat.

Step 2.  Add all the flour and stir until it is a pasty consistency. Return to medium heat and continue stirring for about 1-2 minutes or until dough is glossy and smooth and pulls away cleanly from bottom and sides of the pan
Step 3.  Transfer the dough to a stand mixer fitted with a paddle attachment. Mix on low speed for about 30 seconds to release some steam. Slowly add the eggs 1 at a time, letting the dough absorb each addition before adding more. 
 Once all the eggs are added continue mixing to thoroughly combine the eggs to the dough.  If you lift the paddle it should form a triangle dangling from the paddle.  It should hold its shape and not break off. If the dough is too stiff, add a little more egg.
Step 4. It is now ready to pipe! Transfer dough to a piping bag fitted with a large round tip. You have a couple options for piping.  If you have mad piping skills, just line a baking sheet with parchment or a silpat and pipe small uniform rounds onto the sheet, leaving about 2 inches between each circle.  When piping the rounds leave the tip in place holding it straight up and pipe to "flood" the area. When they are about the size of a quarter, stop squeezing and do a slight twist with the bag so it doesn't look like a Hershey kiss.  If it does, just wet your finger and smooth it out by hand.
(I piped these by hand)
Or as an alternative Keller solution if you don't have mad piping skills:
Buy silicone molds that are mini muffin sized.  Pipe the Pate a Choux into the molds filling each cavity.  Dip your fingers in water to smooth out the tops.  Cover the mold with plastic and freeze until firm enough to easily remove the dough from the molds.  Remove from the mold and place on a lined baking sheet about 2 inches apart just like pictures above. Spay the cream puffs lightly with water.

For the cookie:
Step 1. Combine the brown sugar, flour, and almond flour in a stand mixer fitted with a paddle attachment. Mix until all lumps are broken up and the two ingredients are combined.  Add the butter and mix on medium speed until butter is combined and it looks crumbly. It will not form a solid mass.

Step 2. Pour crumb mixture onto a large piece of parchment paper. (you may want to divide this between 2 different pieces of parchment paper) Using your hands, squeeze together the crumbs to form a dough. (it will still be crumbly). Take a second piece of parchment paper that is the same size and place on top of crumbs. (so crumbs are between the 2 pieces of parchment) Roll out so it is square and 1/4 inch thick. Transfer to the back of a cookie sheet and freeze for about 10 minutes.
Remove the dough from the freezer and roll again to 1/16-1/8th inch thick. If gaps or holes form, just patch them with the crumbs from the edge. Freeze again until frozen solid.
 Step 3. Using a round cutter that is the same size as your cream puff, cut rounds from the cookie and place on top of each cream puff.

Preheat the oven to 375.  Place the baking sheet on the center rack and immediately lower the temperature to 350.  Bake for 25-30 minutes, or until golden brown. If baking 2 sheets at once, rotate the pans half way through baking.  

Here is a picture of the finished product again.
Let these cool completely, then you can fill them.  What you fill them with is entirely up to you.  Traditionally for it to be a "cream puff" you would fill it with pastry cream.  They can also just be filled with whipped cream or even ice cream.  Really, anything with the word cream in it. Lemon curd is also good... Ganache.... buttercream.....are you getting any ideas yet?  Get crazy creative here. 
You can fill them 2 ways:
#1- You can cut off the top with a bread knife and pipe the filling in the base, then place the top back on top of the cream filling.  This allows you to put more filling in it and you can also see what's inside.
#2- Poke a hole in the bottom of the puff and with a piping bag squeeze the filling in the hole until the whole inside is filled. 

Either one is fine, you'll just get different looks with each one. Shoot, try them both and see what you  like best. 

Thursday, September 13, 2012

How to poach an egg

Egg poaching is one of those things that is so easy its hard.  Its really not that complicated, yet everyone is afraid to try it.  Here are the tricks to easy, perfect poaching!

Side note: Before I get to the steps I want to address regular Joe schmo eggs vs. cage free vs. free range.  There is a huge difference in taste and how the egg cooks up between the different varieties.  I'm a little bit of an egg snob. I only buy organic free range eggs.  Love them. Happy birds=yummy eggs. I had to the other day eat {gulp} a Joe schmo egg and I could instantly tell the difference.  The egg didn't have as much flavor and it wasn't as firm.   Don't bother with the caged free...that does not mean they are roaming around outside. It just means they are not in a cage. They are still kept indoors with no light and crammed in and coop with a million of their friends. Not worth paying the extra moola.

Step 1: Use the freshest eggs possible. The egg whites lose a lot of its strength as it ages. Have you ever cracked open an egg and the whites ran EVERYWHERE?? That my friend is a not so fresh egg.

Here is how you tell if your egg is fresh..... put it in water. If the egg sinks and stays on its side.....its fresh. If the ends point up its ok, but not at its best.  If it floats.....use it for scrambled eggs or hard cooked eggs, its not so fresh.

{sinks and stays on its side...... that's a good egg}
Not so fresh doesn't mean bad though. Like I mentioned, those not so fresh eggs are actually perfect for hard cooked eggs.  They are still "good" {not spoiled} they just don't have any elasticity to the egg white.  When hard cooking an egg that is actually a good thing because it means the peel will slide right off. Don't you hate it when you need to make deviled eggs and the shell sticks and pulls half the white off with it and they look all ugly? Yeah, your eggs are too fresh.

Step 2: Crack the egg into a small bowl and add 4 tablespoons of white vinegar. Let it sit for about 10 minutes. The acid in the vinegar will help the whites to firm up faster which means less loss of the thin white when it cooks.  This makes a HUGE difference. As an alternative if you need to do a bunch of these and don't want to dirty a million bowls, you can just add about a 1/2 cup vinegar to the poaching water after it comes to a boil, but I like the individual bowls better.

 Step 3: Use a pot, not a saute pan.  The deep water helps keep the white together as it drops vs. with a saute pan the only direction the egg has to go is it spreads more instead of wrapping the white around the yolk. Salt your water and bring it up to a simmer.  Back the heat down so it is steaming but not bubbling.

Step 4:  There's a couple techniques you can use to add the egg to the water.  
First method: Do one at a time and swirl the water with a spoon to create a whirlpool in the center.
 Pour the egg into the center and as the water spins it will force the white to wrap around the yolk. Keep stirring the water for about 10-20 seconds or until you see the white start to set up.
 Let the egg cook for exactly 1 1/2 to 2 minutes tops depending on how firm you like your white. I get gaggy when the white is slimy so I go 2 minutes and it is perfect! Nice, runny yolk.... no gaggy slimy white.
I did this egg as an example of why I like the soaking in vinegar method over just adding the vinegar to the water.  This one was with the vinegar in the water, no pre-soak.  You can see how the egg white is mostly together, but the edges are kind of scraggly. Not horrible, but not beautiful
 Here is a finished picture of the egg soaked in vinegar for 10 min. before cooking:
 See how much nicer it looks and how it wraps itself in the white and is nice and oval? Perfect!

{Here's a side by side of both eggs. Left is no vinegar soak and right is with the vinegar soak.}

As an alternative......If you need to do a bunch and don't have the time to do one at a time, its ok to poach 3-4 at a time.  They will separate in the water.
 Repeat with the other 1-2 eggs adding one at a time. Let the previous egg slightly set up for a few seconds before adding the other eggs so they don't all flow together. You may need to use a spoon to push the white over the yolk a little because it will try to spread slightly. I don't like this as much because the shape of the egg won't be as nice as the swirl and will look like this on the edges:

Step 5:  This is the coolest step.  Eggs need to be eaten pretty quickly after cooking.  If you are making several of these, the cooking one at a time method will mean eggs sitting and waiting for the others to finish. That will lead to overcooked, cold eggs.  Dunk the cooked egg into an ice bath to stop the cooking. This is great for breakfast in the morning when you don't want to take the time to do all these steps! Do it the night before and they will keep for a day in the fridge and can be re-warmed by submerging it in hot water for about 15 seconds right before you're ready to actually eat it.

This is my favorite breakfast food ever and the greatest thing ever to do with a poached egg: Eggs Benedict!
Use a toasted English muffin or piece of crusty bread like a baguette and layer a couple pieces of Canadian bacon, the egg, then top with hollandaise sauce.  I love to add a little dill and dijon mustard to my hollandaise for this dish.  MMMMMMmmmm.

Wednesday, May 9, 2012

100% Honey Whole Wheat Pullman bread

A couple months ago I bought a pullman pan.  
Since then I've been on a quest for the perfect 100% whole wheat pullman recipe.  Pullman pans are simple.  For a 13 inch pan you need a 3 pound dough recipe. Simple. If you're doing a white loaf.  Whole wheat bread usually is cut with 1/2 white flour, or there are additional weird ingredients like dehydrated potato flakes, nonfat milk solids, gluten, etc. Whole wheat flour doesn't rise very well because the wheat cuts through the gluten, which is why all the extra stuff.  I don't want the extra stuff in my sandwich loaf.  I played with a few recipes and had the expected rising issues, but also they were dry, and didn't have a good texture (crumb).  I finally tried a recipe from this book:

Finally found the  perfect 100% whole wheat pullman sandwich loaf.  Soft texture, moist, with a perfect crust.  And no weird ingredients.

The recipe is the 100% whole wheat honey loaf on page 10
* The amounts have been changed to 1.5 the books listed recipe to fill a 13 in pullman pan.  Also the book gives you several options of how to mix the dough (mixer, food processor, bread machine).  I always use a mixer so this is the method I'll be showing you how to do.

2 cups whole milk
4 1/2 Tbs Honey
3 Tbs Butter, softened
3 tsp. Salt
3 cups Whole wheat flour
3 cups Whole wheat bread flour
3 tsp. Active dry yeast

Step 1: Mixing and fermenting

Heat the milk slightly (about 105 degrees).  Pour into the bowl of a mixer and add the honey and yeast. Let it stand for about 5 minutes until the yeast bubbles.   Add the butter, salt, whole wheat flour, and 1/2 the bread flour. Mix until combined.  Cover and let stand for 15 minutes. 

 Add in the remaining bread flour and with a mixer fitted with a dough arm knead the dough on medium speed until the dough is smooth and springy.  (about 10 min)
 Cover the bowl and let double in volume (about 1 hour). 

Step 2: Shaping

Turn the dough out onto a lightly floured cutting board. Punch the dough down and roll into a rectangle the length of the pan. 
 Fold the top of the rectangle toward the center, press to seal the edge.
 Fold the bottom of the rectangle to the top to make a cylinder.
Lightly grease the pullman pan and place the dough in the pan seam side down and cover with the lid. Let the dough rise until its about 1 inch away from the top of the pan.

 Bake at 400 degrees with the lid on for 30 minutes.  Uncover and bake an additional 10 minutes until the loaf is golden brown and cooked through.  Immediately turn the loaf out of the pan onto a cooling rack and let cool thoroughly.
Since there's only 2 in our house there is no way we would ever finish this whole loaf in a reasonable amount of time.  This loaf freezes well.  I cut it in half and wrap it in plastic wrap then put it in a freezer ziplock bag.  Just pull it out of the freezer when you need it and it will thaw pretty quickly. It will still be nice and soft and moist with no staling.

Monday, April 23, 2012

Bouchon French Macaroons

Recipe from Thomas Keller's Bouchon book, page 310 & 311
Makes between 31-36 finished cookies

I went to France a few years ago and my most memorable and treasured moments on the trip were eating real French food. Specifically real French croissants and macaroons.  I was in absolute heaven the whole time. The macaroons in France are seriously to die for. I always had my 2 euro coin ready so I was able to quickly pop into any bakery we passed during the tours and grab one, then I would run to catch up to the group.  It was a shame that they stale so quickly otherwise I would have brought back a years supply when I left.  I've tried making these many MANY times since and have figured out one thing about macaroons:

They have some massive PMS issues.

They're so moody and seem like they only turn out right when they feel like it.  I've tried several different recipes and have had issues with all of them.  Batter too runny, they don't develop "feet", they aren't shiny, they crack on top..... I can go on all day with the possible problems with these.  Christmas 2010 I went to Yountville, CA during our Christmas escape and stopped at the Bouchon bakery.  I swear angels sang that day.  They had French macaroons.  Amazing French macaroons.  The closest I've ever tasted to the real French macaroons in the states.  Not surprising though.  If you know me, you know of the mad crush I have on Thomas Keller.  Everything he makes is fantastic.  His recipes and methods never fail.  He did live and work in France for a while.  I suppose that helped a little in his awesomeness. But anyways, I've had both his French Laundry and Bouchon book for a while and I wanted to kick myself that I didn't realize his macaroon recipe was in the Bouchon book. I've had his secret piece of heaven in my house this whole time and never realized it.  I love the Bouchon book because he specifically wrote it so people could make his recipes at home. He even tested it in a regular persons home kitchen to make sure they worked. Oh they work....they ALWAYS work.  I have never had a single problem with any of his recipes. Can't stress enough of how much everyone should have this book in their kitchen.

 Anyways.... on with the show! Here is the recipe and tricks of making the best french macaroons you will ever have in your life. I hope after reading this you all have the confidence to give these a try at home.

This is a three part process:
#1- making the cookie
#2- making the butttercream
#3- putting it all together

Part 1: The Cookie

5 cups Almond Flour
5 3/4 cups Confectioners (powdered) Sugar
1 1/4 cups egg whites (7-8 large eggs), room temperature
2 Tbs. + 1 tsp. sugar
pinch cream of tartar
2 tsp vanilla

Oven temperature:
325 degrees
Making the cookie is usually the most challenging part.  I had zero problems with this recipe.  You can find almond flour in most specialty stores like whole foods.  Whole food's almond flour is actually really great.  Its nice and fine which is important in making macaroons because it contributes to the final texture of the cookie.  You can also find almond meal at Trader Joe's which is pretty much the same thing.  Almond meal is a little coarser and the almond skins are pretty visible, which give it more texture and its looks a little more rustic.  I just pulsed it for a few seconds in my food processor to make it a little finer and it worked perfectly.  Don't pulse it too much or you'll end up with almond butter.

Step one:
Combine the almond flour and confectioners sugar in a large bowl and mix well.  Add that mixture in batches to the food processor and pulse for about 10-15 seconds.  Dump that into a large bowl and repeat until all of the mixture has been processed. This step will make the texture a lot finer and lighter.  (note: Most recipes have you sift this a million times but this recipe doesn't call for that and didn't need it.  SO glad to be able to skip that step.) 
 DON'T SIFT! No matter how much you want to. I don't know why you would want to though.

(Almond flour and Confectioner's sugar in the food processor)

 (Almond flour and Confectioner's sugar in the large bowl after processing)

Step 2:
Place the egg whites in the bowl of a mixer fitted with a whisk attachment. Make sure you don't get any (not even a small speck) of egg yolk in the whites when separating otherwise they will not inflate. Whisk on high speed just until the whites get frothy and hold a shape.  Slowly sprinkle in the sugar and cream of tartar (with the machine running).
Continue whisking until egg whites are at stiff peaks.  In case you don't know what peaks are.... here you go:

(soft(ish) Peak. I would say this is more between soft and medium peak.)

 (Medium Peaks)

(firm peaks)
Be very careful not to over-whip the whites.  They will look grainy and watery instead of smooth and shiny if you do whip too them too far.

Step 3:
Fold 1/4 of the almond flour/sugar mixture into the whipped whites. Fold just until combined then add the vanilla and fold until the vanilla in incorporated. It should still be nice and fluffy.
Add this to the bowl of flour/sugar and fold together. It may seem dry at first but keep folding and it will come together.  Folding is not stirring. Don't stir this. Here's what it should look like when its all combined.

Step 4: Pan it up! 
I've seen these come in all sizes small and large.  Its hard to get a good balance of chewy and crispy.  T.K has tested this and found that 2 inch cookies yielded the best results.  I agree. As a self proclaimed macaroon junkie who's eaten a million macaroons, these had the best texture of any I have ever eaten.  A trick to make sure all of the cookies are actually 2 inches and all the same size: Use a 2 inch round cookie cutter and trace around that onto the parchment paper.  This made it so easy to pipe these out.

Its very important that you use a heavy duty half sheet pan (or any heavy duty cookie sheets) on these otherwise the pan gets too hot for the cookies and they can crack on top. If you don't have a heavy duty pans you can just double up 2 sheet pans. Measure parchment paper to fit a half sheet pan. You must use parchment paper! Target sells it. Go get some and keep it in your kitchen at all times.  Wax paper is NOT parchment paper.  You will need 4 sheet pans and 4 pieces of parchment paper.  Trace around the cookie cutter on the parchment paper keeping spacing 1 inch apart.  Trace four circles on one row, then 3 circles below spacing between the circles above.  Repeat until you have 3 rows of 4 and 2 rows of 3.  Make sure the ink side of the parchment paper is facing down on the pan so the cookies don't cook in ink.

Fill a pastry bag fitted with a 1/2 inch plain tip with the macaroon batter.  This is the easiest method ever:
Pace the bag into a quart cup (or any tall cup) with the tip pointing up so the batter doesn't come out while filling. Fold the bag over the top of the cup and fill it up! Clean and less awkward then trying to hold it and fill at the same time.
Hold the bag in the center of one of the circles about a 1/2 inch above the circle. Leave the tip in place the entire time and squeeze the bag to "flood" the circle with the batter. Don't move the bag around. Just leave it in the center and it will fill the whole circle.

 After all cookies are piped, gently tap the pan on the counter to smooth them out and get rid of any peaks left by the pastry bag.  Repeat with all 4 cookie sheets.
 I ended up only having enough batter to fill 3 1/2 sheets even though there was supposed to be enough for 4 whole pans.  They were the perfect size so I don't think I over filled them. 

This last step is super important:
Let the cookies rest at room temperature for 1-2 hours. I let mine sit for the full 2 hours and I'm glad I did.  They need to dry out and the tops should form a crusty skin.  

After 2 hours preheat the oven to 325 and bake 1 sheet at a time.  T.K. says it's ok to do 2 sheets and rotate shelf positions half way through baking, but my oven cooks so unevenly, doing this in the past has caused nothing but problems. I figure good things come to those who wait.... just do one pan at a time to be safe.

Place the pan on the middle rack and bake for 11 mins. Turn the pan then cook for an additional 10-11 mins.  The signature macaroon "feet" should start forming around 10 mins or shortly after.  When finished they should be light golden brown on the top and bottom with crispy tops.

Leave the cookies on the parchment paper and immediately slide the paper onto a cooling rack to let cool completely. 
Repeat with remaining 3 pans.

Once the cookies are cool, peel the paper away from the cookies. They should easily separate from the paper.

Part 2: The Buttercream

1 1/2 cups sugar
1/2 cup water
4 large eggs
1 pound unsalted butter (cut into small pieces)
1 Tbs. + 1 tsp. Vanilla

Note: make the buttercream while the cookies are doing their 2 hour room temperature rest.

To make "real" buttercream you need one of these:
Or a real candy thermometer. But this one is way better and easier to read and you can use it to temp everything... not just sugar.  This is a kitchen tool I could not live without.

Real buttercream is egg based. Usually meringue. If you have a recipe that just blends confectioner's sugar with butter and vanilla, please throw it out and never use it again.  For some reason when people see that you have to boil sugar to make a good buttercream they freak and think its too hard. Its not hard, its not tedious, and its totally worth a couple extra steps.

Normally, whenever I've made buttercream in the past it uses only the whites of the eggs.  This is the first time I made or even heard of making buttercream with the whole eggs.  I was a little nervous about this because I couldn't imagine why it would work.  Egg yolks deflate whites. How would it get that traditional thick and creamy consistency?  It works.  Never doubt The Keller. It's so rich and creamy and is the best I've ever had. Probably wouldn't be great for frosting because its a little softer then Italian meringue buttercream, but its a perfect filling.

Step 1:
Combine the sugar and water in a sauce pot.  Gently stir just to dissolve the sugar.  If you splash any on the sides of the pan just brush it with a wet pastry brush to clean the sides.

 Let it boil on moderately high heat without stirring it... ever.  Let it be.  If you stir it you will cause crystallization, which is bad.  Place the thermometer stem in the sugar and let it cook until it reaches 248 degrees. 

Step 2:
While the sugar is boiling, beat the eggs on high speed in a mixer with a whisk attachment.  They should be thick and frothy by the time the sugar reaches 248.  It should look like this:

Step 3:
Reduce the mixer speed and pour the syrup into the eggs being careful to stay to the side and not pour it into beater.  That would fling the sugar onto the side of the bowl instead of mixing it with the eggs.   Continue to mix until the mixture thickens and cools to room temperature.  

Step 4:
Feel the sides of the bowl with your hands. It should feel cool to the touch.  Its very important that the bowl be cool before adding the butter.  If the eggs are too hot it will melt the butter and you will have a soupy consistency.  If that happens, just put the bowl in the fridge for about 10 minutes to slightly harden the butter, then continue mixing. Add the butter a handful of chunks at a time, whisking to combine. 

It should come together pretty quickly.  If the mixture separates or breaks, just keep mixing it.  It will eventually come back together.

I call this the scrambled egg stage.  Right before its done mixing it briefly looks like scrambled eggs.  This is normal and good. That means you did it right and it's a few seconds away from being perfect.  I remember the very fist time I made buttercream I saw this stage and thought I screwed up and threw it out because it looked funny. Whoops.

Finished product! It should be smooth and creamy at this point and not look like scrambled eggs anymore. Add the vanilla and stir well to combine it all together.

Now here is where you can have some fun with this.  You can actually add any flavored extract you want in place of the vanilla.  Or if you want to get really crazy you can add a few ounces of melted chocolate to it, or my FAVORITE..... pistachio.  Peel about 3/4-1 cup of pistachios and blend them in a food processor for about 5-8 minutes until it forms a paste

Then whisk the paste into 1/2 of the buttercream in a separate bowl.

Part 3: Put it all together

Fit a pastry bag with a small round tip and fill with the buttercream.  I did one sheet pan at a time.  There are 18 cookies on each pan so turn 9 of the cookies over and pipe a large dollop (about a tablespoon or so) into the center of the cookie leaving a little bit of a border.

Then place another cookie on top top and gently press down.  The filling will press out the the edge of the cookie.

As a variation I left some of the butter cream plain vanilla and put a little bit of strawberry jam (about a teaspoon) on top of the buttercream. (Strawberries and cream!)

 Put the top on and you're ready to eat.

Extra notes:
 These really are at their peak flavor and texture on day 1.  If you aren't going to eat them that day, don't fill them all.  (Or even better, if you don't need the full batch of 36, reduce the recipe to make what you can use in 1-2 days) Store the unfilled cookie shells in an airtight container and they should keep for several days.  The buttercream should be stored covered in the refrigerator.  Just bring it to room temperature and whip it a little before using it. The buttercream can be stored for a couple weeks in the fridge or in the freezer for up to a month.  Its important to keep the filled cookies at cool room temperature. If they get too warm the filling will melt and ooze out.  You can keep them in the fridge, but the buttercream isn't as good when its solid cold and the cookie stales slightly and isn't as chewy.  If they need to be kept cool in the fridge, at least let them come back to room temperature before eating.
You also may have noticed I didn't color the Pistachio cookies.  I don't like artificial colors.  Green food dye does not make it taste like pistachio.  I can see the visual appeal of having colored shells, but it really adds nothing more than just that visual appeal.  So I passed and left them plain colored. To each their own though. If you want them to be colored, just add a few drops of food color paste (not the liquid) until its the color you want.