For The Ladyfingers:

Preheat oven to 400 degrees F (205 degrees C). Line two 17 x 12 inch baking sheets with baking parchment. Fit large pastry bag with a plain 1/2 inch round tube.

Place egg whites in bowl and beat on high until soft peaks start to form. Slowly add 2 tablespoons of the sugar and continue beating until stiff and glossy. In another bowl beat egg yolks and remaining sugar. Whip until thick and very pale in color.

Sift flour and baking powder together on a sheet of wax paper. Fold half the egg whites into the egg yolk mixture. Fold in flour, and then add the remaining egg whites. Transfer mixture to pastry bag and pipe out onto prepared baking sheet. Bake 8 minutes.

For The Tiramisu:

In a medium saucepan, whisk together egg yolks and sugar until well blended. Whisk in milk and cook over medium heat, stirring constantly, until mixture boils. Boil gently for 1 minute, stirring constantly. Remove from heat, whisk until the consistency of pudding. Cover tightly and chill in refrigerator at least 1 hour.

In a medium bowl, beat cream with vanilla until stiff peaks form. Whisk mascarpone into yolk mixture until smooth. Use an electric hand mixer for the best results. Fold whipped cream into the yolk mix. In a small bowl, combine espresso and Kahlua. Split ladyfingers in half lengthwise and dunk in coffee mixture. Arrange a layer of soaked ladyfingers in bottom of a 8x8 inch dish. Spread a layer of the mascarpone filling over the soaked ladyfingers. Repeat layers until dish is full and sprinkle heavily with cocoa. Cover and refrigerate for 24-48 hours for best flavor, and to allow time to set.