01 - Whisk egg yolks with powdered sugar in a heatproof bowl over a pot of simmering water (double boiler) for 2–3 minutes until thick and pale. Remove from heat and cool slightly.
02 - In a separate bowl, beat the cold heavy cream until stiff peaks form.
03 - Gently fold mascarpone into the cooled egg mixture until smooth. Then fold in the whipped cream until fully combined.
04 - In a shallow dish, mix cooled coffee with coffee liqueur.
05 - Quickly dip each ladyfinger into the coffee mixture (1–2 seconds per side), ensuring they are moistened but not soggy. Arrange half of the dipped ladyfingers in a single layer in an 8-inch square dish.
06 - Spread half of the mascarpone mixture evenly over the ladyfingers.
07 - Repeat with another layer of dipped ladyfingers, then the remaining mascarpone mixture.
08 - Cover with plastic wrap and refrigerate at least 4 hours, or overnight for best results.
09 - Before serving, dust generously with cocoa powder and garnish with chocolate shavings if desired.