Ingredients

• 1 1/2 cups flour, plus additional for dusting the work surface
• 3/4 cup cocoa powder, preferably Dutch-process
• 1 teaspoon baking powder
• 1/4 teaspoon salt
• 3/4 cup unsalted butter, cool, cut into small pieces (6 ounces)
• 1 cup sugar
• 1 1/4 teaspoons fresh ground black pepper
• 1/4 teaspoon ground allspice
• 1 large egg, at room temperature
• 2 teaspoons vanilla extract
• 2 tablespoons confectioners' sugar

Instructions

1. In a medium bowl, mix the flour, cocoa powder, baking powder and salt until well combined. Set aside.

2. Using a stand mixer on medium speed, soften the butter, about 1 minute. Add the sugar and beat until light and fluffy, if still a little gritty, about 2 minutes. Beat in 3/4 teaspoon of the pepper and the allspice. Scrape down the sides of the bowl, then beat in the egg and vanilla extract until smooth, about 1 minute. Reduce speed to low and stir in the flour mixture, just until combined.

3. Lightly dust the work surface with flour and turn the dough onto it. Roll gently into a 9-inch log, wrap in plastic and refrigerate until firm, about 3 hours.

4. Position oven racks in the upper and lower thirds of the oven and preheat the oven to 375 degrees. Line 2 baking sheets with parchment paper or Silpat liner.

5. Slice the log into 1/4-inch-thick pieces and place them about 1 inch apart on the prepared baking sheets. Bake for 6 minutes, then rotate the baking sheets top to bottom and front to back. Bake for about 6 more minutes, or until the cookies are slightly puffed and the tops feel springy. Cool for 2 minutes on the baking sheets, then transfer the cookies to racks to cool completely.

6. In a small bowl, mix the confectioners' sugar with the remaining 1/2 teaspoon black pepper. After all of the cookies are cooled, sift the sugar-pepper mixture over the cookies through a fine-mesh strainer. Store in an airtight container at room temperature between layers of wax paper for up to 5 days or freeze for up to 3 months.