I'm a newcomer to the site, and therefore a latecomer to the August tiramisu discussion, but for what it's worth I'll contribute an entirely different approach to tiramisu and see if anyone recognizes it. This is a Tuscan recipe from an Italian friend who collects "typical" local recipes, and it differs from what we eat over here by being a pudding in a cup, rather than a layered dessert. (Note: You can buy Pavesini at the Italian shop in Chelsea Market, and I highly recommend this variation.)
4 egg yolks
6 tbsp sugar
1 lb mascarpone
1 pint heavy cream, beaten to stiff peaks
1/2 lb sponge cake (or 20 ladyfingers or 40 Pavesini)
2 cups espresso
3 tbsp cocoa powder
1. Beat the egg yolks with the sugar until smooth and fluffy (about 15 mins by hand; 5 with mixer). Cook the entire mixture in a double boiler over hot water, stirring constantly, until 160 degrees. Never stop stirring, or the eggs will curdle. Transfer immediately to a bowl and cool to room temperature and continue to stir to prevent the mixture from curdling.
2. Add the mascarpone to the yolks and beat until well blended and velvety. Fold into the whipped heavy cream.
3. Dip the sponge cake (or ladyfingers or Pavesini biscuits) briefly in the coffee so that both sides are wet. Place on a plate to drain.
4. Arrange the drained cakes/biscuits on the bottom of four 4-inch diameter ramekins or glass serving dishes. If using ladyfingers or Pavesini, line the cups with them. Fill the center with the mascarpone cream mixture, sprinkle with cocoa and refrigerate for two hours before serving. Makes four 6-ounce servings.