- 1 1/2 cups all-purpose flour
- 3/4 cup unsweetened cocoa powder
- 1 cup plus 2 tablespoons sugar
- 1/4 teaspoon salt
- 1/4 teaspoon baking soda
- 12 tablespoons (1 1/2 sticks) unsalted butter, slightly softened
- 3 tablespoons skim milk
- 1 teaspoon pure vanilla extract
Combine the flour, cocoa, sugar, salt, and baking soda in the bowl of food processor and pulse several times to mix thoroughly. Cut the butter into about 12 chunks and add them to the bowl. Pulse several times. Combine the milk and vanilla in a small cup. With the processor running, add the milk mixture and continue to process until the mixture clumps around the blade or the sides of the bowl. Transfer the dough to a large bowl or a cutting board and knead a few times to make sure it is evenly blended.
Form the dough into a log about 14 inches long and 1 3/4 inches in diameter. Wrap the log in wax paper or foil and refrigerate until firm, at least one hour, or until needed.
Position the racks in the upper and lower thirds of the oven and preheat the oven to 350°F. Line the baking sheets with parchment paper. Cut the log of dough into slices as thin as you can, about 1/8-inch thick. and place them one inch apart on the lined sheets (cookies will spread). Bake, rotating the baking sheet halfway through baking, for a total of 8 to 12 minutes. The cookies will puff up and deflate; they are done about 1 minute after they deflate.
Note: These cookies should crisp as they cool. If they don’t, you’re not baking them long enough— in which case, return them to the oven to reheat and bake a little longer, then cool again.
From Smitten Kitchen