Peanut Butter Sandwich Cookies

• For the cookies
• all-purpose flour↗6 ounces
• cake flour↗2 ounces
• baking soda↗1⁄2 teaspoon
• salt↗1⁄4 teaspoon
• unsalted butter, completely softened at room temperature↗6 ounces
• smooth peanut butter↗3⁄4 cup
• sugar↗1⁄2 cup
• firmly packed light brown sugar1⁄2 cup
• pure vanilla extract↗1 teaspoon
• large egg↗1
• For the filling
• confectioners' sugar↗1 1⁄2 cups
• unsalted butter, softened at room temperature↗3 ounces
• smooth peanut butter↗3⁄4 cup
• tablespoons heavy cream↗3
• cup coarsely chopped roasted unsalted peanuts1⁄4
• cup coarsely chopped semisweet chocolate or 1/4 cup miniature semisweet chocolate chips↗1⁄4

Step-by-step instructions

1. 1

   To make the cookies: Heat the oven to 350°F

2. 2

   Line two baking sheets with parchment. In a medium bowl, sift together the two flours, baking soda and salt.

3. 3

   In the bowl of an electric mixer, cream the butter, peanut butter and sugars with the paddle attachment until light and fluffy. Add the vanilla and egg; continue creaming until smooth, about 3 minutes with an electric mixer (longer by hand). Stir in the flour mixture by hand just until it's incorporated; don't over mix or the cookies will be tough. Drop heaping tablespoonfuls of batter, spaced about 2-inches apart, onto the lined baking sheets. With floured fingers, flatten each dab of batter into a 2-inch round.

4. 4

   Bake until the cookies are puffed and golden, 12- 14 minutes, rotating the baking sheets if needed for even baking. Transfer the cookies to a rack to cool.

5. 5

   While the cookies cool, make the filling: In a small bowl, cream the confectioners' sugar, butter and peanut butter until smooth. Add the heavy cream; continue creaming until smooth and fluffy. Stir in the chopped peanuts and chocolate.

6. 6

   To assemble: Transfer the cooled cookies to a work surface, flipping half of them over. With an offset spatula or a butter knife, spread a scant teaspoon of filling onto each turned-over cookie. Set another wafer on top of each filled cookie, pressing gently to spread the filling. Store sealed at room temperature or in the refrigerator.