6 eggs, separated
1 cup sugar
1/4 cup rum
1/4 cup coffee liqueur
1/2 vanilla bean
1 teaspoon ground cinnamon
16 ounces Mascarpone
1 1/2 - 7 ounce packages ladyfingers
2 cups brewed strong coffee
1. In the bowl of an electric mixer, beat the egg yolks and 1/2 cup of sugar until thick and very light, about 2 minutes. Add the rum and coffee liqueur and beat until smooth. Split the vanilla bean and scrape the seeds into the egg yolk mixture. Add the Mascarpone and cinnamon and beat until evenly combined. Reserve this mixture.
2. In a clean mixer bowl, beat the egg whites until frothy. With the mixer running, gradually add the remaining 1/2 cup of sugar and beat to stiff peaks. Gently fold the beaten egg whites into the reserved egg yolk mixture until evenly combined.
3. Cover the bottom of a 9 x 13-inch pan with a single layer of ladyfingers. Brush the ladyfingers with coffee until soft but not mushy. Spread half of the mascarpone filling over the ladyfingers. Repeat with another layer of ladyfinger, soaked with coffee, and mascarpone filling.
4. Sprinkle the surface of the tiramisu with unsweetened cocoa powder and chill for at least 2 hours before serving.