Preheat your oven to 350°F (175°C). Grease an 8×8-inch baking pan and line it with parchment paper.

In a mixing bowl, whisk together the gluten-free flour, baking powder, salt, and cocoa powder. Set aside.

In another bowl, mix the granulated sugar, brown sugar, and melted butter until well combined. Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract and the cooled coffee.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Pour the brownie batter into the prepared pan, spreading it evenly. Bake for 20-25 minutes, until a toothpick inserted in the center comes out with a few moist crumbs.

While the brownies are cooling, beat the mascarpone cheese until smooth.

In a separate bowl, whip the heavy cream and powdered sugar until stiff peaks form.

Gently fold the whipped cream into the mascarpone mixture until fully combined.

Once the brownies are cooled, spread the mascarpone layer evenly over the top.

Dust with grated dark chocolate or cocoa powder if desired.

Refrigerate the brownies for at least 2 hours to set before cutting them into squares and serving.