Step 1: Make the Cheesecake Layer
Preheat oven to 325°F (163°C).
Grease and line the bottom of a 9-inch (23 cm) springform pan with parchment paper.
In a large bowl, beat cream cheese until smooth. Add sugar and beat until creamy.
Mix in eggs one at a time, followed by sour cream and vanilla.
Pour into the prepared pan and bake for 45–50 minutes, or until the center is set.
Cool completely, then wrap in plastic and freeze for at least 2 hours for easier assembly.
Step 2: Make the Red Velvet Cake Layers
Preheat oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
In a bowl, whisk together flour, sugar, baking soda, salt, and cocoa powder.
In another bowl, whisk oil, buttermilk, eggs, food coloring, vinegar, and vanilla until smooth.
Gradually add dry ingredients to wet, mixing until just combined.
Divide batter evenly between pans and bake for 25–30 minutes.
Cool completely before assembling.
Step 3: Make the Cream Cheese Frosting
Beat cream cheese and butter until creamy.
Gradually add powdered sugar and vanilla, beating until fluffy.
Step 4: Assemble the Cake
Place one red velvet cake layer on a serving plate.
Carefully remove cheesecake from the pan and place it on top.
Add the second red velvet cake layer.
Frost the entire cake with cream cheese frosting.
Chill for at least 1 hour before slicing.