Step 1
Preheat oven to 350 degrees F (175 degrees C). Place a pan of hot water in the bottom of the oven.
Step 2
Line two 9-inch springform pans with aluminum foil; grease with cooking spray.
Step 3
Beat cream cheese in a bowl with an electric mixer until smooth about 3 minutes. Add 1 1/2 cup white sugar and cornstarch; beat until smooth. Add 1 tablespoon vanilla extract. Beat in 2 eggs and 2 egg whites 2 at a time until batter is creamy. Add heavy cream; beat just until batter is free of lumps and fluffy.
Step 4
Divide batter between the prepared pans.
Step 5
Bake in the preheated oven until edges appear set about 40 minutes. Turn off oven; leave cheesecakes inside for 1 to 2 hours. Chill until firm at least 4 hours or overnight.
Step 6
Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9-inch round cake pan.
Step 7
Whisk buttermilk and 3/4 teaspoon vanilla extract together in a small bowl.
Step 8
Whisk flour cocoa powder cinnamon baking soda and salt together in a separate bowl.
Step 9
Beat 1 1/4 cup white sugar and oil with an electric mixer until creamy. Whisk in 2 eggs one at a time. Add vinegar and red food coloring; beat well. Beat in flour mixture in 3 additions alternating with buttermilk mixture until batter is smooth. Pour batter into the prepared pan.
Step 9
Bake in the preheated oven until a toothpick inserted into the center comes out clean about 50 minutes. Cool for 10 to 15 minutes in the pan. Invert onto a wire rack. Cut horizontally into 2 even layers. Chill until firm at least 4 hours to overnight.