Mix the egg yolks with sugar, stirring lightly with electic mixer until you obtain a smooth paste.
Mix the egg whites until stiff, in a separate bowl. Combine the egg whites into the mixture of egg yolks and sugar, stirring constantly, then add mascarpone, a bit at a time.
Place a layer of aligned lady fingers (after being dunked in coffee) on the serving plate, then cover with cream and grated chocolate.
Continue alternating layers of lady fingers and cream, decorating to finish with sprinkling of grated chocolate.
Fridge for 3 hours or overnight is the best. Serve cold!
