Place mascarpone, egg yolks and sugar in a bowl and mix until well blended and smooth. Add a little coffee flavouring or coffee liquor to the cheese mixture, and a little to the coffee.

Dress a loaf tin with plastic wrap.

Put half the cheese mixture into the tin. Then quickly dip the sponge fingers into the coffee and layer on the cheese. Spoon the remaining Mascarpone on the sponge fingers and finish off with another layer off dipped sponge fingers.

Cover with plastic wrap and chill in refrigerator for at least a couple of hours. When ready to serve turn out onto a plate and grate dark chocolate over the top.