Layers of red velvet cake and creamy baked cheesecake finished with cream cheese frosting. Make the cheesecake layer ahead and freeze it before assembling for clean layers.
Preheat the oven to 325°F. Spray a 9-inch springform pan, line the bottom with parchment, and wrap the outside tightly with foil. Bring water to a boil for the water bath.
Beat the cheesecake cream cheese until smooth. Add sugar and salt; blend about 2 minutes. Add eggs one at a time, then mix in sour cream, heavy cream, and vanilla.
Pour into the springform pan. Set it in a roasting pan and add hot water halfway up the sides. Bake 45 minutes. Cool at room temperature for 1 hour, then freeze completely before assembly.
Preheat the oven to 350°F. Spray two 8-inch cake pans. Whisk the cake flour, cocoa, baking soda, and salt together.
Cream the cake butter and sugar. Beat in eggs one at a time, then add oil, vinegar, vanilla, buttermilk, and red food coloring. Fold in dry ingredients until smooth.
Divide the cake batter between the pans and bake 25–30 minutes, until a toothpick comes out clean. Cool 10 minutes on a rack, then remove from pans.
Beat frosting cream cheese, butter, and vanilla for 2 minutes. Add sifted powdered sugar and beat until fluffy.
Level the cake layers. Place one cake layer on a serving plate, center the frozen cheesecake on top, then add the second cake layer. Frost the whole cake. Finish with crumbled cake scraps and, optionally, grated white chocolate. Slice and serve.