Prep: 20 minutes
Bake: 9 to 10 minutes per batch
Freeze: 1 hour, 30 minutes
Makes: About 18 cookies, enough for 9 sandwiches
Note: Adapted from "Cookies & Cream," by Tessa Arias. The dough is somewhat sticky; we found it easier to handle after chilling it for 30 minutes.
1 cup plus 2 tablespoons flour
1/4 cup plus 2 tablespoons unsweetened Dutch-process cocoa powder
3/4 teaspoon baking soda
1/2 teaspoon fine sea salt
1 1/2 sticks (12 tablespoons) unsalted butter, at room temperature
3/4 cup sugar
2 large eggs
1/2 teaspoon vanilla
1. Heat oven to 375 degrees. In a medium bowl, sift together flour, cocoa, baking soda and salt. In a separate bowl, beat butter and sugar with an electric mixer at medium-high speed until smooth and well combined, 1-2 minutes. Beat in eggs and vanilla. On low speed, gradually add flour mixture; beat until combined. Refrigerate, 30 minutes.
2. Drop 2 tablespoon-size balls of dough onto parchment-paper lined baking sheets. Slightly flatten each. Bake 9-10 minutes, rotating sheets halfway through baking. Cool on baking sheets 5 minutes; transfer to wire racks. Cool completely. Freeze cookies until firm, at least 1 hour.
3. To assemble, top 1 cookie with a scoop of slightly softened ice cream. Top with another cookie. Gently press down to form a sandwich. Wrap the sandwich in parchment or wax paper; freeze immediately. Repeat with remaining cookies. Freeze at least 1 hour before serving.
Pick a favorite cookie recipe. Drop cookies are easy to work with, says Arias, who uses a 2-tablespoon, spring-loaded ice-cream scoop, then rolls the scooped dough in her hands to smooth before flattening slightly and baking. Try: chocolate chip, oatmeal, peanut butter or gingersnap cookies.
Egan uses brownies (chocolate or butterscotch baked in larger pans so they're thinner), plus madeleines, meringues and coconut macaroons.
Purchase good-quality cookies.