Prepare the Espresso Mixture: In a shallow bowl, combine the espresso, cocoa powder, and vanilla extract. Whisk until blended.

Mix the Mascarpone Base: In a mixing bowl, beat egg yolks and sugar until thick. Gradually fold in mascarpone until smooth.

Whip the Heavy Cream: Whip the heavy cream until soft peaks form, then fold into the mascarpone mixture.

Assemble the Ladyfingers: Dunk ladyfingers quickly in the espresso mixture and lay them in a baking dish.

Layer the Mascarpone Mixture: Spread half of the mascarpone mixture over the ladyfingers and dust with cocoa powder.

Repeat the Layering Process: Dunk the remaining ladyfingers, layer them, and cover with the remaining mascarpone mixture and cocoa powder.

Chill to Perfection: Cover and refrigerate for at least 2 hours or overnight before serving.