Make the Cake Base

1. Preheat oven to 350°F (176°C). Prepare a 9 inch springform pan with a circle of parchment paper in the bottom and grease the sides. If your springform pan leaks, then you’ll want to use a 9 inch cake pan for the cake layer.
2. In a medium sized bowl, combine the flour, sugar, cocoa, baking soda, baking powder and salt. Whisk until well combined.
3. In another medium sized bowl, combine the milk, vegetable oil, vanilla extract and egg white. Whisk until well combined.
4. Add the dry ingredients to the wet ingredients and whisk together until well combined.
5. Add the water and whisk until well combined. The batter will be thin.
6. Pour the batter into the prepared pan and bake for 12-15 minutes, or until a toothpick inserted in the middle comes out clean.
7. Remove cake from the pan and set on a cooling rack to cool.
8. Reduce the oven temperature to 300°F (148°C). If you used a springform pan, clean the pan, put it back together and respray the sides with non-stick spray. You want to be sure it’s well done so that they cheesecake doesn’t stick to the sides after baking. Line the bottom with parchment paper. If you used a cake pan for the cake layer, set up your springform pan with non-stick baking spray on the sides and parchment paper on the bottom. Cover the outsides of the pan with aluminum foil so that water from the water bath cannot get in (see how I prepare my pan for a water bath). Set prepared pan aside.

Make the Cheesecake Filling

1. In a large bowl, beat the cream cheese, sugar and cocoa powder on low speed until well combined and smooth. Be sure to use low speed to reduce the amount of air added to the batter, which can cause cracks. Scrape down the sides of the bowl.
2. Add the sour cream and vanilla extract and mix on low speed until well combined.
3. Add the melted chocolate in three parts, stirring until combined after each. Adding it in parts helps ensure that it incorporates evenly and helps prevent clumping.
4. Add the eggs one at a time, mixing slowly to combine after each addition. Scrape down the sides of the bowl as needed to make sure everything is well combined.
5. Add the cooled cake layer to the bottom of springform pan and add the chocolate cream cheese filling to the pan, on top of the cake layer.
6. Place the springform pan inside another larger pan. Fill the outside pan with enough warm water to go about halfway up the sides of the springform pan. The water should not go above the top edge of the aluminum foil on the springform pan.
7. Bake for 1 hour, 15 minutes. The center should be set, but still jiggly.
8. Turn off the oven and leave the door closed for 30 minutes. The cheesecake will continue to cook, but slowly begin to cool as well.
9. Crack the door of the oven for 30 minutes to allow the cheesecake to continue to cool slowly. This process helps prevent cracking.
10. Remove the cheesecake from the oven and water bath wrapping and refrigerate until firm, 5-6 hours or overnight.

Add the Toppings

1. Once completely cool and firm, remove the cheesecake from the springform pan and place on a serving plate.
2. To make the whipped cream, add the cream, cocoa powder, powdered sugar and vanilla extract in a large mixing bowl and whip on medium speed until stiff peaks form. It will happen quickly.
3. Pipe the whipped cream onto the outer edge of the cheesecake, the finish it off with sprinkles if desired. Refrigerate until ready to serve.