Sandwich Cookie Filling Recipes

Steps:

• With an electric mixer on medium-high speed, beat butter until smooth. Add confectioners' sugar, and beat until light and fluffy. Stir in one of the flavorings. Use immediately.

Steps:

• Set 2 racks in the middle and upper third of the oven and preheat to 375 degrees. In a food processor or the bowl of an electric mixer, thoroughly mix together the flour, cocoa, baking soda, baking powder, salt and sugar. While pulsing or on low speed, add the butter, then the egg. Process or beat until the dough is thoroughly blended and massed together. Drop rounded teaspoons of batter onto nonstick or parchment-lined cookie sheets at 2-inch intervals. With moistened fingers, round out the cookies and flatten them a little. Bake for 9 minutes, turning the pans once for even baking, until the cookies are set. Set the cookie sheets on a rack to cool.
• Vanilla-Cream Filling: Put the butter and shortening in a mixing bowl and, at low speed, gradually beat in the confectioners' sugar and vanilla, until blended. Turn the mixer up to high and beat for 2 or 3 minutes more, until fluffy.
• With a pastry bag fitted with a 1/2-inch tip, pipe teaspoon size blobs of filling onto the tops of half the cookies. Keeping the smooth bottoms of the cookies facing up, flip the remaining cookies on top of the filling and lightly press to form sandwiches.

Steps:

• Make the cookies: In a stand mixer with the paddle attachment, beat the butter, granulated sugar, and brown sugar until creamy, scraping down the sides of the bowl as needed. Mix in the milk and vanilla.
• In a medium bowl, thoroughly combine the flour, cocoa, salt, and baking soda. Slowly add to the butter mixture while beating on a low speed. Add chocolate chips, if using, and mix until just combined. When evenly mixed, shape the dough into a log about 2 inches thick and roll it in wax paper. Chill in the refrigerator for at least 2 hours or overnight.
• Preheat the oven to 350 degrees F.
• Use a sharp knife to slice the cookies into 1/3-inch-thick disks. Don't worry if cookies break apart as you cut them--pieces can be stuck back together and will bake fine. Arrange 2 inches apart on baking sheets lined with parchment paper. Bake until set, 10 minutes. Cool for a few minutes on the baking sheets, and then remove to racks to cool completely.
• Make the filling: Set aside half of the chopped pistachios for garnish. Mix the remaining pistachios with the confectioners' sugar, mascarpone cheese, ricotta, vanilla, and salt until just blended; do not overbeat, as the mascarpone will get too thick. Cover and refrigerate until needed.
• To assemble, put a scoop of filling on the bottom side of a cookie and top with the bottom side of another cookie, so that there is about 1/4 inch of filling in each sandwich. Coat the filling edges with the reserved pistachios.