01 - Whisk egg yolks and granulated sugar together in a large bowl until mixture becomes pale and thick.
02 - Blend mascarpone cheese into the egg mixture, stirring until completely smooth.
03 - Beat heavy cream separately until firm peaks form, then gently fold into mascarpone mixture.
04 - Mix cooled espresso and coffee liqueur in a shallow dish.
05 - Dip ladyfinger biscuits briefly into the coffee solution, ensuring they absorb liquid without becoming overly soggy.
06 - Arrange a layer of soaked ladyfingers in the bottom of a square 9-inch dish. Spread half the mascarpone cream evenly over the ladyfingers.
07 - Top with the remaining soaked ladyfingers and finish with the remaining mascarpone cream, smoothing the surface.
08 - Sift unsweetened cocoa powder over the top layer to evenly cover.
09 - Cover and refrigerate for a minimum of 4 hours to ensure flavors meld and dessert sets properly.