In a KitchenAid, beat egg whites until stiff.

In another bowl, beat egg yolks and ⅓ cup sugar until thick and pale yellow. Add in mascarpone cheese until combined, and continue beating another minute or so. Add in kahlua, and mix until smooth.

Gently fold in egg whites until combined.

In a small bowl wide enough to dip cookies into, combine the espresso and 1 tablespoon sugar. Set aside.

To assemble small cups: Dip the first cookie in the espresso-sugar mixture until almost fully saturated but not falling apart. Break in half and place the halves in the bottom of a cup. Spoon 1 generous tablespoon cream over it. Dust with cocoa powder. Dip second cookie in coffee and break in half. Place side-by-side over cocoa then top with 2 generous tablespoons cream mixture, which should take you nearly to the top of the cup. Dust with more cocoa. Repeat with remaining cups.

To assemble large cups: Dip first cookie in espresso mixture until almost fully saturated but not falling apart. Break in half and place side-by-side in the bottom of your larger cup. Spoon 2 generous tablespoons cream over and dust with cocoa powder. Repeat 2-3 layers in each cup.

 Let the cups chill for at least 3 hours, or at preferably overnight, in the fridge to set. Before eating, you can dust them with fresh cocoa powder for a prettier look.