- 1 stick (1/2 cup) unsalted butter, softened
- 1/4 cup superfine granulated sugar
- 1/2 teaspoon vanilla
- 1/8 teaspoon salt
- 3/4 cup all-purpose flour
- 1/4 cup unsweetened Dutch-process cocoa powder
- Blend butter, sugar, vanilla, and salt in a bowl with a fork until combined well. Sift flour and cocoa into butter mixture and blend with fork just until mixture forms a soft dough.
- Divide dough in half and pat out with floured fingertips into 2 (6- to 6 1/2-inch) rounds on an ungreased large baking sheet. Chill dough, uncovered, until firm, about 30 minutes.
- Preheat oven to 375°F while dough chills.
- Prick dough all over with fork and bake shortbreads in middle of oven until centers are dry to the touch and edges are slightly darker, about 15 minutes. Cool on baking sheet on a rack 10 minutes, then cut each shortbread into 8 wedges with a large heavy knife. Transfer to rack to cool.