Combine yolks and sugar in a double boiler.
Cook over low 10 minutes, stirring constantly.
Remove from heat and whip yolks in mixer with whisk for 4 minutes to thicken.
Add mascarpone and mix.
In a separate bowl, beat cream to stiff peaks.
Gently fold cream into yolks and combine. (Sneak a taste-mmmm!)
Grab a 9x11 pan and dip the ladyfingers in coffee and lay in pan across bottom for first layer.
Top with 1/3 of cream.
Repeat for 3 layers until you reach the top.
Grate chocolate with veggie peeler on to the top and chill covered overnight.
adapted from All Recipes