Cream 1 cup of softened unsalted butter with ¾ cup granulated sugar and ¾ cup brown sugar until light and fluffy.

Beat in 2 large eggs one at a time, then add 1 teaspoon of vanilla extract.

Gradually add 2 cups of all-purpose flour combined with 2 tablespoons of espresso powder and 1 teaspoon of baking powder.

Mix until just combined to create a sticky dough.

Cover the bowl with plastic wrap and refrigerate for at least 30 minutes.

Preheat oven to 350°F (175°C) and line a baking sheet with parchment paper.

Scoop rounded tablespoons of dough onto the prepared baking sheet, spacing them about 2 inches apart.

Bake for 10-12 minutes, or until edges are lightly golden and centers are set but still soft.

Let cookies cool on the baking sheet for about 5 minutes before transferring to a wire rack.

Prepare frosting by whipping together 1 cup mascarpone cheese, 1 cup heavy cream, and 2 cups powdered sugar until creamy and thick.

Frost each cooled cookie generously and dust with cocoa powder.

Serve immediately or store in an airtight container.