Whisk together 4 large egg yolks and ½ cup granulated sugar in a heatproof bowl over simmering water for about 10 minutes until pale and thickened. Cool for 15 minutes.

In a separate bowl, beat 1 cup heavy cream until stiff peaks form, about 3-5 minutes. Fold gently into the cooled egg mixture.

Fold in 1 cup mascarpone cheese into the egg and cream mixture until blended carefully.

Prepare a shallow dish with 1 cup cooled espresso and ¼ cup coffee liqueur. Dip ladyfingers for 2-3 seconds and lay them in your serving dish.

Spread half of the mascarpone mixture over the ladyfingers. Add another layer of dipped ladyfingers, topped with the remaining mascarpone mixture.

Cover with plastic wrap and refrigerate for at least 4 hours, preferably overnight for best flavor melding.

Dust with cocoa powder and optionally sprinkle chocolate shavings before serving.