Preheat your oven to 350°F (175°C) and line a standard cupcake pan with paper liners.

Cream together the softened unsalted butter and granulated sugar until light and fluffy, about 3 minutes.

Incorporate eggs one at a time, mixing well after each addition until the mixture is homogenous.

Combine the all-purpose flour and espresso powder in a separate bowl, then gradually add to the wet mixture.

Fold in the milk and strong coffee gently until no dry flour is visible, being careful not to overmix.

Fill each cupcake liner about two-thirds full with the batter and bake for 18 minutes or until a toothpick comes out clean.

Cool the cupcakes in the pan for 5 minutes, then transfer to a wire rack to cool completely.

Prepare the frosting by mixing mascarpone cheese, heavy cream, and powdered sugar until stiff peaks form.

Frost the cooled cupcakes with the mascarpone frosting, using a spatula or piping bag.

Dust lightly with cocoa powder just before serving for a classic tiramisu touch.