- 1/2 cup all-purpose flour
- 1/2 cup sugar
- 1/4 cup unsweetened Dutch-process cocoa powder
- 1/2 tsp baking powder
- 1/4 tsp salt
- 1 tsp espresso powder (optional)
- 2 tbsp unsalted butter, cut into pieces, room temperature
- 1/3 cup (about 3 oz) chopped dark chocolate
- 1 large egg
- 1 tbsp vanilla extract
- 1 cup powdered sugar
- Preheat oven to 375° with racks in center and upper third. Line 2 baking sheets with parchment.
- Whisk together flour, sugar, cocoa powder, baking powder, salt, and espresso powder (if using). Rub butter into dry ingredients until mixture resembles breadcrumbs. Stir in chocolate.
- Whisk together egg and vanilla. Add egg mixture to chocolate mixture; stir with a fork until mixture is slightly moistened. Form dough into a ball; wrap in plastic; refrigerate 30 minutes.
- Shape dough into tablespoon-size balls. Roll each in powdered sugar to coat; place on sheets 2″ apart. Bake until just set but still slightly undercooked, about 10 minutes. Let cool on sheets 5 minutes; transfer to wire racks to cool completely. Serve warm.