Preheat your oven to 350°F (175°C) and gather a 9-inch springform pan alongside an 8-inch round cake pan. Line the bottoms with parchment paper and spray the sides with non-stick spray.

In a mixing bowl, whisk together 2 cups of all-purpose flour, 2 tablespoons of unsweetened cocoa powder, and a pinch of salt. Set this dry mixture aside.

In a large bowl, cream together 1 cup of softened butter and 2 cups of granulated sugar until light and fluffy, about 3-5 minutes. Add in 1 cup of sour cream, 1/2 cup of vegetable oil, 1 tablespoon of vanilla extract, and 2 large eggs, plus 1 tablespoon of red food coloring. Mix well.

Gradually add the dry mixture into the wet batter, alternating with 1 cup of buttermilk. Mix until just combined, then fold in 1 teaspoon of baking soda and 1 teaspoon of vinegar.

Divide the prepared batter evenly between your two pans and bake for 18-20 minutes. Allow to cool completely on wire racks.

While the cakes cool, process 1 1/2 cups of Oreo cookies into fine crumbs. Beat together 16 ounces of cream cheese and the Oreo crumbs until smooth. Mix in 3/4 cup of granulated sugar and 2 tablespoons of cornstarch.

Next, add in 1 cup of sour cream, 1 teaspoon of vanilla, and 2 large eggs (plus 1 egg yolk) to the Oreo mixture. Mix until just combined and fold in 1 cup of crushed Oreo pieces.

Pour the Oreo cheesecake batter over one of the cooled red velvet cake layers in the springform pan. Cover the pan with foil and place it in a water bath. Bake at 300°F (150°C) for about 90 minutes.

Turn off the oven, leaving the cheesecake inside with the door slightly ajar for 1 hour. Refrigerate overnight.

Prepare the ganache by melting 1 cup of dark chocolate chips with 1/2 cup of heavy cream until smooth. Pour over the chilled cheesecake.

Sprinkle crumbled red velvet cake and cream cheese frosting on top before serving.