- 2 tablespoons natural cocoa powder
- 2 teaspoons instant espresso powder
- 1/3 cup plus 1 tablespoon granulated sugar
- 1 sheet puff pastry (half of a 17.3-ounce package), thawed
- All-purpose flour, for the work surface
- 2 tablespoons unsalted butter, melted
- Whisk together the cocoa, espresso powder, and 1/3 cup of the sugar in a bowl.
- Roll the pastry into a 10-by-14-inch rectangle on a floured surface. Brush with the butter, then sprinkle with the sugar mixture; press in the sugar until it is dampened.
- Starting at one long side of the rectangle, roll the pastry toward the center of the sheet, stopping at the middle. Repeat with the opposite end so the rolls meet. Refrigerate until firm, at least 1 hour and up to 2 days.
- Heat oven to 425° F. Line 2 baking sheets with parchment.
- Cut the log into 1/4-inch slices. Place the cookies 1 inch apart on the baking sheets and sprinkle with the remaining tablespoon of sugar. Bake, rotating the sheets halfway through, until golden brown, 10 to 13 minutes. Let cool slightly on the baking sheets, then transfer to a wire rack to cool completely.