These cookies look like little snow-covered mountains. They will keep for up to a week stored in an airtight container at room temperature. Roll each ball in confectioners sugar twice to make sure it's thoroughly coated and no dark dough is visible.
1/2 cup all-purpose flour
1/4 cup unsweetened cocoa powder
4 teaspoons Crio Brü grounds
1 teaspoon baking powder
1/8 teaspoon salt
4 tablespoons unsalted butter
2/3 cup packed light brown sugar
1 large egg
4 ounces bittersweet or semisweet chocolate, melted and cooled
1 tablespoon milk
Confectioners sugar, for coating
In a medium bowl, sift together flour, cocoa, Crio Brü, baking powder, and salt. With an electric mixer, cream butter and brown sugar until light and fluffy. Beat in egg until well combined; mix in cooled chocolate. With the mixer on low, gradually add flour mixture; beat in milk until just combined. Flatten dough into a disk; wrap in plastic. Freeze until firm, about 45 minutes.
Preheat oven to 350 degrees. Line two baking sheets with parchment. Shape dough into one-inch balls. Pour confectioners sugar (about a ½ cup) into a medium bowl; working in batches, roll balls in sugar two times, letting them sit in sugar between coatings.
Place on prepared baking sheets, two inches apart. Bake until cookies have spread and the coating is cracked, 12 to 14 minutes; cookies will still be soft to the touch. Cool cookies on a wire rack.