Prepare the Oreo crumbs and Oreo pieces. I used a food processor for both.
1/2 cup Oreo pieces, 1/4 cup Oreo crumbs
Using a mixer, beat the cream cheese and sugar on high speed for 2 minutes. It will become creamy.
1/2 cup White granulated sugar, 16 oz Cream cheese
Add in the sour cream, heavy cream, and vanilla. Mix on medium speed until smooth. Add in the eggs and mix on low speed until just combined.
1/2 cup Sour cream, 1/4 cup Heavy cream, 1 tsp Pure vanilla extract, 2 Large eggs
Take off the mixer and mix using a baking rubber spatula. Add in the Oreo crumbs and Oreo pieces and mix it in.
Pour 1/3rd of the chocolate cake batter to the prepared pan. Add in 1/3 of the cheesecake batter in dollops around the top. With your eyes, separate the rest of the chocolate cake batter into thirds, add a third of that in dollops on top of the cheesecake.
Repeat with the cheesecake and cake batter. You will end with the chocolate cake batter on top, spread evenly with an offset icing spatula.
Bake for 45-55 minutes until a toothpick inserted comes out with cheesecake crumbs, no raw cake batter. Note: after baking it will look cracked due to the chocolate cake batter rising. After cooling it will sink in the middle a little due to the cheesecake. This is normal!
Place the cake on the wire rack still in the pan. Cool completely. Once cool, cover in foil and chill in the fridge for at least 6 hours or overnight.