Combine the melted butter, sugar, and brown sugar in the bowl of a stand mixer. Mix until combined.

Add the egg and vanilla and mix again.

Slowly mix in the flour, espresso powder, salt, baking soda, and baking powder. Mix thoroughly, scraping down the sides and mixing again.

Measure out 1-inch-sized balls of dough (a heaping tablespoon) - about the size of a ping pong ball - and roll them between your hands to smooth out.

Place on a parchment-lined baking sheet.

Chill for 30 minutes to prevent spreading while baking.

Preheat the oven to 350 degrees. Line the baking sheets with parchment.

Once the cookies have chilled, place them about 2 inches apart on the prepared baking sheets. Bake for about 10-12 or until the edges are slightly browned and the center is set.

Allow the cookies to cool completely before decorating.

Combine the mascarpone cheese, heavy cream, confectioner’s sugar, and vanilla in the bowl of a stand mixer.

Mix on low until combined, about 20-30 seconds.

Increase to medium/high for an additional 1-2 minutes or until stiff peaks form and the frosting holds its shape. Do not over mix or the frosting will deflate.

Chill in the fridge until ready to use.

Transfer the frosting to a piping bag fitted with a large round tip.

Once the cookies have cooled, pipe the frosting on the top of each cookie.

Sprinkle with a dusting of cocoa powder.