Classic Chocolate Whoopie
from Whoopie Pies

1 2/3 cups all-purpose flour
2/3 cup unsweetened cocoa powder
1 1/2 teaspoons baking soda
1/2 teaspoon salt
4 tablespoons unsalted butter, room temperature
4 tablespoons vegetable shortening
1 cup packed dark brown sugar
1 egg
1 teaspoon vanilla
1 cup milk

Preheat oven to 375 degrees. Line baking sheets with parchment paper. In a bowl, sift together, flour, cocoa, baking soda, and salt. In another bowl, beat butter, shortening and sugar with a mixer on low until just combined. Increase speed to medium and beat for about 3 minutes. Add egg and vanilla and beat for two more minutes. Add half of the flour mixture and half of the milk and beat on low until incorporated. Repeat with remaining flour and milk and beat until combined. Using a tablespoon, drop batter on baking sheet two inches apart. Bake for about 10 minutes each or until pies spring back when pressed gently. Remove from oven and cool for about five minutes before transferring them to a rack to cool completely.

1 Tbsp of batter should make about 48 two-inch cakes or 24 pies.
2 Tbsp of batter should make about 30 four-inch cakes or 15 pies.

Salty Peanut Butter Filling
from Whoopie Pies

3/4 cup creamy peanut butter (or crunchy)
3/4 cup unsalted butter, room temperature
3/4 cup confectioners sugar
1/2 teaspoon salt

Beat peanut butter and butter on low until creamy using a mixer. Add sugar and salt and beat on low to incorporate. Increase speed to medium and beat for about four minutes until the filling is light and fluffy. Spread filling on flat side on one cooled cake. Top it with a second cake and press gently.

Store whoopie pies in an airtight container.