Preheat oven to 325°F. Wrap a 9-inch springform pan tightly with aluminum foil and place into a deep roasting pan. Place a parchment circle in the bottom of the pan and set aside.

Bring a kettle of water to a boil as you prepare cheesecake batter.

In a large bowl, beat cream cheese on medium speed until smooth. Add sugar and beat until incorporated. Add eggs, one at a time and beat after each addition. Add sour cream, heavy cream, salt, and vanilla bean seeds/paste. Beat until smooth.

Scrape batter into prepared springform pan. Place on rack in middle of oven. Pour boiling water from kettle into roasting pan so that water comes halfway up the sides of the springform pan.

Bake in preheated oven for 45-50 minutes, until completely set. Remove from oven. Remove springform pan from roasting pan and discard foil. Cool on wire rack until completely cool then transfer to freezer. Freeze until completely solid, at least 4 hours or overnight.

Preheat oven to 350°F. Grease and flour two (9-inch) cake pans. Line the bottoms with a parchment circle. Set aside.

In a large bowl, whisk together flour, sugar, cocoa powder, baking soda, and salt. Set aside. In a large bowl, whisk together eggs, oil, buttermilk, food coloring, vanilla extract and vinegar. Add the wet ingredients to the dry ingredients and beat with a hand mixer on medium speed until evenly combined. Divide evenly between two cake pans.

Bake in preheated oven for 30-35 minutes, until a tester inserted into the center comes out clean. Remove from oven and cool in pan 10 minutes. Remove cakes from pans and cool completely on wire racks.

In a large bowl, beat cream cheese and butter together on medium speed until smooth and creamy. Add powdered sugar and vanilla seeds/paste. Beat again just until smooth and creamy again.

Place one red velvet layer on a cake plate. Remove cheesecake from freezer, remove sides of springform pan and invert cheesecake layer on top of red velvet layer. Remove parchment circle. Top with second red velvet layer. Trim sides of cakes to make even all around.

Apply a thin very layer of frosting over top and sides of cake. Refrigerate cake for 30 minutes. Then frost cake with remaining frosting. Garnish, if desired.