chocolate tuxedo cake

This is a hit whenever I make it, it is a favorite to take to parties!!

White Cheesecake Layer
1 1/2 lb cream cheese - softened
2 cup confectioner's sugar (powdered sugar)
1/2 cup sour cream
1 tsp vanilla extract
6 oz white baking chocolate - melted and cooled
2 envelopes unflavored gelatin
1/4 cup cold water

Chocolate Layers
1 1/2 cup semisweet chocolate chips
1/2 cup butter - softened
1/2 cup granulated sugar
2 lg eggs
1 tsp vanilla extract
1 1/2 cup all-purpose flour
1 tsp baking soda
1/2 tsp salt
1 cup sour cream

Chocolate Sour Cream Frosting
1 1/3 cup semisweet chocolate chips
6 Tbsp butter
2/3 cup sour cream
1 tsp vanilla extract
3 cup confectioner's sugar

FOR THE WHITE CHOCOLATE CHEESECAKE LAYER:
Beat cream cheese with confectioners sugar until smooth. Blend in sour cream, vanilla extract and white chocolate. Stir the gelatin into the cold water in a small saucepan and allow mixture to stand several minutes to soften. Then heat mixture gently over a low setting until thoroughly dissolved. Cool briefly, then blend into the cream cheese mixture. Line bottom of a 9-inch spring form pan with foil, then coat pan and foil well with a nonstick spray. Pour mixture into prepared pan, cover top of pan and chill until firm.
This cheesecake layer can be prepared up to two days in advance, and held in the refrigerator.

FOR THE CHOCOLATE LAYERS:
Melt chocolate chips in a small heavy gauge saucepan over low heat. Remove from heat and cool slightly. Preheat oven to 350F and arrange rack to the center position. Grease and flour two 9-inch round cake pans. Cream the butter with the sugar until very light and fluffy. Add the eggs, one at a time, beating well after each addition. Stir in the vanilla extract and the cooled, melted chocolate. Whisk the flour with the baking soda and salt and gradually stir into the batter. Blend in the sour cream and divide batter evenly between the two prepared pans. Bake at 350F about 25 minutes or until layers spring back when lightly pressed in their centers. Cool layers in pans 10 minutes, then loosen and turn out onto a rack to complete cooling.

Makes Two 9-inch layers

CHOCOLATE SOUR CREAM FROSTING:
Melt chocolate chips and butter in a small, heavy gauge saucepan over low heat, stirring until smooth. Transfer mixture to a large mixing bowl and cool 10 minutes. Stir in sour cream and vanilla extract. Gradually add confectioners sugar, beating until frosting is smooth.

TO ASSEMBLE THE CAKE:
Arrange one of the cooled chocolate cake layers in center of a cake plate, top side down. Placing top side (because of its moist surface) down will help to secure cake to plate, preventing layers from slipping after cake is assembled. Release rim of the spring form pan. Holding cheesecake in one hand and chocolate cake layer (on plate) in other hand, quickly invert chocolate layer (plate and all) on top of the cheesecake. Quickly flip the two, now attached layers back over, so chocolate layer is again on bottom. Now, you can easily remove spring form pan bottom from (now top) of cheesecake layer. Arrange the remaining chocolate cake layer (top side down) on top of cheesecake layer. Using a long sharp knife and a slight sawing motion, carefully cut around rim of cheesecake layer to make it even with chocolate layers. Frost sides and top of cake and serve. The cheesecake layer will hold at room temperature several hours.

For best results, serve cake within 3 hours of assembling. Refrigeration will cause the frosting to loose its beautiful sheen.