• Preheat the oven to 350℉ (175℃). Line a 12-cup muffin tin with cupcake liners.

MAKE THE CUPCAKES

• In a bowl whisk together the flour, baking powder and salt. Set aside.
• In another bowl, beat the butter and sugar together until light and fluffy. Add the eggs and vanilla and mix well to combine.
• Alternately add the flour mixture and the milk to the wet ingredients, starting and ending with flour. Mix until just combined.
• Stir the cooled espresso coffee into the mixture.
• Fill the cupcake liners about 3/4 full and bake for 18-20 minutes, or until a toothpick comes out clean. Remove cupcakes from the oven and cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

MAKE THE COFFEE SYRUP

• Heat the espresso and sugar in a small saucepan until the sugar has dissolved. Remove from the heat and stir in coffee liqueur (if using).
• Using a skewer or fork, poke holes in each cupcake and brush the cupcake tops with the coffee syrup to soak in the coffee flavor.

MAKE THE FROSTING

• In a large bowl beat the heavy cream until soft peaks form.
• In a separate bowl whip mascarpone cheese, powdered sugar, and vanilla until smooth.
• Gently fold the whipped cream into the mascarpone mixture until combined.

ASSEMBLE

• Pipe or spread the mascarpone frosting on top of the cooled, coffee cupcakes. A Wilton 1M tip is good for this.
• Dust with cocoa powder and garnish with chocolate shavings if desired.
• Store leftover cupcakes in an airtight container in the fridge for up to 3 days. Bring to room temperature before serving.