From Martha Stewart’s Cookies Cookbook.
(This is for the whole recipe, I only made half though)
For the cookies:
3 1/2 cups all-purpose flour
1 1/2 cups unsweetened cocoa powder
1 tablespoon baking soda
1 teaspoon baking powder
1 teaspoon salt
2 sticks (1 cup) unsalted butter, at room temperature
2 cups sugar
2 large eggs
2 cups buttermilk
2 teaspoons pure vanilla extract
In a large bowl mix butter and sugar until pale & fluffy. Add remaining ingredients and combine well.
Gradually add flour mixture and stir to combine. Drop by tablespoon onto parchment or Silpat lined baking sheets, spacing 2 inches apart. Bake for 8 minutes, rotating sheets half-way through. Remove from oven, cool completely on wire rack.
For the filling:
1 1/3 cups natural, creamy peanut butter
2 sticks (1 cup) unsalted butter at room temperature
1 1/2 cups confectioner’s sugar
Cream together peanut butter & butter, add sugar and mix to combine. Once cookies are cooled completely, spread 1 tablespoon filling onto the flat side of one cookie, sandwich with another cookie.