Preparation

Step 1: Prepare the Dry Ingredients

1. Preheat the oven to 350°F (175°C).
2. Grease and flour two 9-inch (23cm) round cake pans. Line the bottoms with parchment paper for easy release.
3. In a medium bowl, whisk together the all-purpose flour, cocoa powder, baking soda, baking powder, and salt. Set aside.

Step 2: Cream the Butter and Sugar

4. In a large mixing bowl, beat the softened butter and granulated sugar using an electric mixer on medium speed until light and fluffy (about 3–4 minutes).

Step 3: Add Wet Ingredients

5. Add the eggs, one at a time, beating well after each addition.
6. Mix in the vanilla extract, white vinegar, and vegetable oil (or melted butter if substituting).
7. Reduce the mixer speed to low and add the buttermilk, alternating with the dry ingredients. Begin and end with the dry ingredients. Mix until just combined.

Step 4: Add the Color

8. Stir in the purple gel food coloring, adjusting the amount to achieve the desired shade of purple. If using natural colors, blend blueberry reduction and beet juice for a rich purple tone.

Step 5: Bake the Cake

9. Divide the batter evenly between the prepared cake pans.
10. Smooth the tops with a spatula and bake for 30–35 minutes or until a toothpick inserted in the center comes out clean.
11. Let the cakes cool in the pans for 10 minutes before transferring them to a wire rack to cool completely.

Step 6: Prepare the Cream Cheese Frosting

12. In a large bowl, beat the softened cream cheese and butter together until smooth and creamy.
13. Gradually add the powdered sugar, one cup at a time, while mixing on low speed.
14. Stir in the vanilla extract and heavy cream. Beat until smooth and fluffy.

Step 7: Assemble the Cake

15. Place one cake layer on a serving plate and spread a generous layer of cream cheese frosting on top.
16. Place the second cake layer on top and frost the entire cake with the remaining frosting.
17. Smooth the frosting with an offset spatula and decorate as desired.