Chocolate Marshmallow Whoopie Pies

Makes 24 sandwich cookies

For the cookies:
3½ cups all-purpose flour
1 tsp. salt
1½ cups unsweetened cocoa powder
1 tbsp. baking soda
1 tsp. baking powder
1 cup (2 sticks) unsalted butter, room temperature
2 cups sugar
2 large eggs
2 cups buttermilk, at room temperature
2 tsp. vanilla extract

For the filling*:
1 cup (2 sticks) unsalted butter, at room temperature
2 cups confectioners' sugar, sifted
7½ oz. jar marshmallow fluff
2 tsp. vanilla extract

1. Preheat the oven to 400˚ F.  Combine the flour, salt, cocoa powder, baking soda, and baking powder in a medium bowl; whisk together to blend.  Set aside.  Line two baking sheets with silicone baking mats or parchment paper.  In the bowl of an electric mixer fitted with the paddle attachment, combine the butter and sugar.  Beat together on medium-high speed until light and fluffy, 2-3 minutes.  Beat in the eggs one at a time, blending well after each addition.  Blend in the buttermilk and vanilla extract until incorporated.  Mix in the dry ingredients, blending just until combined. 

2. Using a 1-oz dough scoop, drop the batter onto the prepared baking pans, 12 cookies per pan.  Bake for 12 minutes, rotating the pans halfway through baking.  Allow to cool on the pan 5-10 minutes, then transfer to a wire rack to cool completely.  Repeat with the remaining batter. 

3. To make the filling, place the butter in the bowl of a mixer fitted with the paddle attachment.  Beat on medium-high speed until smooth, 1-2 minutes.  Blend in the confectioners' sugar until incorporated.  Beat in the marshmallow fluff and vanilla until light and fluffy, 2-3 minutes. 

4. Once the cookies are completely cooled, match them up in pairs by size.  Fill a pastry bag fitted with a plain with the marshmallow filling.  Pipe a dollop of marshmallow filling onto the flat side of one cookie of each pair, and sandwich the cookies together, pushing the filling to the edges.  Store in an airtight container. 

*If you tend to be a generous cookie-filler like I am, consider making 2 batches of filling. I'd hate for you to run out.

Adapted from Annie's Eats
Printed from Playing House (www.playinghouseblog.com)