Gluten-free baking is scientific, with lots of math involved. When attempted at high altitude it also involves laborious recipe testing. Okay, that kinda sounds fun to me but it is not something I usually attempt. I start with tried-and-true gluten-free recipes and tweak then just a bit to compensate for altitude. Not today. Today I threw caution to the wind and made every type of substitution possible … all at once … with fingers crossed. Luckily I was successful.

The massive changes I made were based on science, so that dialed down the luck factor. I started with a gluten-free cookie recipe from Bob’s Red Mill then used America’s Test Kitchen cookbooks as a reference for substitutions. I didn’t have all of the flours listed in the recipe so, armed with knowledge from the Test Kitchen, I made swaps based on what was in my cupboard. I added aquafaba and soy milk powder for enhanced vegan structure, as well as guar gum. Granulated sugars were used instead of liquid sweetener so the cookies wouldn’t be too mushy. The last step was to sandwich my cookies with a rich chocolate filling, because life can always be more decadent.

Peanut Butter and Chocolate Cookie Sandwiches loosely based on a recipe from Bob’s Red Mill Everyday Gluten-Free Cookbook

for the cookies:
1/2 cup teff flour
1/4 cup brown rice flour
1/4 cup tapioca starch
1/3 cup potato starch
1 teaspoon soy milk powder
1/2 teaspoon baking soda
1/4 teaspoon fine sea salt
1/4 teaspoon guar gum
1/2 cup + 2 TBS creamy peanut butter, salted but unsweetened
1/2 cup vegan sugar
1/2 cup vegan light brown sugar
1/2 cup neutral-tasting vegetable oil
1 tablespoon aquafaba
3 tablespoons non-dairy milk
for the chocolate filling:
1/3 cup vegan margarine
3 cups vegan powdered sugar
1/2 cup cocoa powder
1/2 teaspoon vanilla extract
1-3 tablespoons non-dairy milk

For the cookies: Whisk the flours, starches, milk powder, baking soda, salt, and guar gum together in a medium bowl. In a large bowl, whisk together the peanut butter, sugars, oil, aquafaba, and 3 tablespoons milk. Add the dry ingredients to the wet ingredients and stir to combine. Cover the dough bowl with plastic wrap and put aside for 30 minutes to rest.

Meanwhile, line two large baking sheets with parchment paper. Place oven racks in the upper-middle and lower-middle positions, and heat the oven to 350F.

When the 30 minutes rest time has passed, scoop out small balls of cookie dough, 2-3 teaspoons in size, and place them about 2 inches apart on the baking sheets. (The dough will be moist and slightly sticky.) Flatten the dough balls with the palm of your hand.

Bake the cookies until golden brown and firm, 14-16 minutes, rotating the cookie sheets halfway through baking time. Let the cookies cool on the sheets for five minutes, then remove to wire racks to fully cool. Repeat with remaining cookie dough.

For the filling: Place the margarine in the bowl of a stand mixer and beat on medium speed for 1 minute. Add the powdered sugar, cacao powder, and vanilla and beat for another minute. Keep beating, adding milk as needed, until the filling is light and fluffy. Fill a pastry bag with the filling.

To assemble the cookie sandwiches: Place half of the cookies upside down on a tray. Pipe filling onto the center of each cookie. Top each with a remaining cookie, pressing down gently until the filling spreads to the edges. Store assembled cookies in an airtight container for up to 3 days.

Until next time, happy baking!