In a wide bowl, combine espresso, liqueur, and brandy. Using a food processor or hand grater, grate chocolate and set aside.
Combine egg yolks and sugar in the top of a double boiler. Using an electric mixer on medium, beat until just fluffy. Place the pan over hot water, not bubbly, and continue to beat until egg mixture is pale yellow and leaves a trail in the mixer's path. Remove from heat and keep beating for 2 minutes. Set aside to cool.
In a large bowl, stir vanilla into the mascarpone. Add egg mixture to mascarpone, folding until the mixture is blended.
Set out a deep baking dish. Dip ladyfingers in coffee mixture until each is moist, but not soaked. Place each dipped ladyfinger into the baking dish until ½ the ladyfingers have been used. You should have an even layer of ladyfingers at the bottom of the dish. Spread ½ the mascarpone mixture over the ladyfingers. Sprinkle with ⅓ of the chocolate. Repeat process with another layer of dipped ladyfingers and the rest of the mascarpone, plus another⅓ of the chocolate. Carefully cover dish and refrigerate until chilled.
When it's time to serve the tiramisu, combine espresso powder and cream in a bowl. Stir until coffee begins to dissolve. Add sugar and beat with a mixer on high speed until stiff peaks form. Spread whipped cream over tiramisu and sprinkle with the rest of the chocolate. Cut with a sharp knife or spatula to serve.