Preneath oven to 475°.
Grease a 9-inch springform pan.
Find a large baking pan big enough to fit the springform pan. Fill the pan with 1/2 - inch of water. Place in the oven while it preheats.
Beat the cream cheese in a large bowl until light and fluffy.
Gradually add the sugar, sour cream, and vanilla, mixing well.
Add eggs one at a time, beating the mixture until just blended.
Fold in the peanut butter cups, then put the batter into the springform pan.
Bake 15 minutes, then reduce the heat to 350°m baking until the center is completely set, about 60 minutes.
Remove the cake from the oven and let it cool for an hour before removing the side of the springform pan.
When completely cool, refrigerate the cheesecake for at least 6 hours. (* hours to overnight is best.)
When completely cold, cut the cheesecake in half horizontally, to make 2 layers
Meanwhile, make the chocolate cake: sift the flour, sugar, cocoa, baking soda, and salt together in a large bowl.
Mix in the eggs, buttermilk, melted butter, and vanilla, beating until smooth.
Slowly add the coffee, blending in well.
Grease and flour 2 9-inch round cake pans. Pour the batter evenly into each pan.
Bake 30 to 35 minutes.
When fully cooked, remove the cakes from the oven and cool for 15 minutes before taking them out of the pans.
When fully cooled, wrap each cake in plastic wrap and refrigerate until ready to assemble the cake.
Make the buttercream frosting by beating the butter and the shortening together, add the peanut butter and vanilla.
Mix in the powdered sugar one cup at a time until you reached the desired sweetness and consistency.
To assemble, put one layer of the chocolate cake on a cake plate.
Drizzle half of the dulce de leche over the top of the cake.
Top that layer with a layer of the cheesecake, and spread the peanut butter frosting over the top of the cheesecake.
Repeat to make a second layer.
When assembled, place the whole cake in the freezer for about an hour to fully set.
Make the ganache by melting chocolate chips with heavy cream and vanilla in a small saucepan.
When the cake is completely set, pour ganache over the top.
Refrigerate until the ganache sets.
