Prepare the Coffee Mixture: Combine the coffee with coffee liqueur (if using) in a shallow bowl. Let cool if still warm.

Make the Cream Mixture: • In a mixing bowl, whisk egg yolks and sugar until the mixture becomes pale and creamy (about 5 minutes). • Gently fold in the mascarpone until smooth. • In a separate clean, dry bowl, beat the egg whites until stiff peaks form. • Carefully fold the beaten egg whites into the mascarpone mixture to keep it light and airy.

Assemble: • Quickly dip each ladyfinger in the coffee mixture, soaking each side briefly. • Layer half of the dipped ladyfingers in the bottom of the 8x8 dish. • Spread half of the mascarpone mixture over the ladyfingers. •Repeat with another layer of dipped ladyfingers and top with the remaining mascarpone mixture.

Chill: Cover and refrigerate for at least 4 hours (preferably overnight) to let the flavors meld.

Serve: Before serving, dust the top with cocoa powder.