1. Preheat oven to 325°F (160°C). Grease a 9-inch springform pan and line the bottom with parchment paper.

2. In a medium bowl, whisk together flour, cocoa powder, and a pinch of salt.

3. In another bowl, whisk sugar, oil, egg, buttermilk, vinegar, vanilla, and red food coloring.

4. Combine dry ingredients with wet ingredients and stir until smooth. Pour into prepared pan.

5. Bake red velvet layer for 20–22 minutes, or until a toothpick comes out clean. Let it cool in the pan.

6. For the blackberry compote: In a saucepan, cook blackberries, sugar, and cornstarch over medium heat until thickened. Cool completely.

7. For the cheesecake layer: Beat cream cheese until smooth. Add sugar, then blend in sour cream and vanilla. Add eggs one at a time, mixing gently.

8. Pour cheesecake batter over the cooled red velvet layer. Smooth the top.

9. Drop spoonfuls of blackberry compote on top and swirl gently with a toothpick.

10. Wrap the pan in foil and place it in a water bath. Bake for 50–60 minutes until edges are set but the center jiggles slightly.

11. Turn off the oven, crack the door open, and let the cheesecake rest inside for 1 hour.

12. Remove and let cool at room temperature. Then refrigerate for at least 4 hours or overnight.

13. Once chilled, slice and serve with additional blackberry topping or fresh whipped cream if desired.