Chocolate Crackle Cookies

Martha has yet to steer me wrong, at least when it comes to food. These are incredibly good, with a delicate texture and a rich flavor that means one cookie is really all you need. On the other hand, they're small, so who's counting?

Do use really good baking chocolate for these; you won't regret it. These are always among the last cookies I bake for the holidays, since the confectioners sugar coating means you can't freeze them afterward.

Ingredients

8 ounces bittersweet chocolate, coarsely chopped
1 1/4 cups unbleached all-purpose flour
1/2 cup unsweetened Dutch-process cocoa powder
2 teaspoons baking powder
1/4 teaspoon kosher salt
1/2 cup (1 stick) unsalted butter, softened
1 1/2 cups packed light-brown sugar
2 large eggs
1 teaspoon pure vanilla extract
1/3 cup whole milk

1 cup granulated sugar
1 cup confectioners' sugar

Instructions

1. Preheat oven to 350 degrees F. 
2. Melt chocolate in a heatproof bowl set over a pan of simmering water, stirring. Set aside, and let cool. 
3. Sift together flour, cocoa powder, baking powder, and salt in a medium bowl; set aside.
4. Mix butter and brown sugar on medium speed until pale and fluffy, 2 to 3 minutes. 
5. Mix in eggs and vanilla, and then the melted chocolate. 
6. Reduce speed to low; mix in flour mixture in 2 batches, alternating with the milk. 
7. Divide dough into 4 equal pieces. Wrap each in plastic; refrigerate until firm, about 2 hours.
8. Divide each piece into 16 (1-inch) balls. Roll in granulated sugar to coat, then in confectioners' sugar to coat. Space 2 inches apart on baking sheets lined with parchment paper.
9. Bake until surfaces crack, about 14 minutes. Let cool on sheets on wire racks. Cookies can be stored between layers of parchment in airtight containers up to 3 days.