Ingredients:

  • 315g all-purpose flour
  • 300g granulated sugar
  • 10g unsweetened cocoa powder
  • 5g baking soda
  • 3g fine sea salt
  • 240ml buttermilk, room temperature
  • 60g full-fat Greek yogurt
  • 180ml vegetable oil
  • 2 large eggs, room temperature
  • 5ml white vinegar
  • 10ml vanilla extract
  • 2 tsp royal purple gel food coloring
  • 225g cream cheese, softened
  • 115g unsalted butter, softened
  • 300g powdered sugar, sifted
  • 5ml vanilla bean paste
  • 2ml lemon juice

Instructions:

  1. Preheat your oven to 350°F (175°C). Grease two 8-inch round cake pans and line the bottoms with parchment paper.
  2. Sift together the 315g flour, 300g sugar, 10g cocoa, 5g baking soda, and 3g salt into a large bowl.
  3. In a separate medium bowl, whisk the 2 eggs with 180ml oil until pale. Slowly stream in the 240ml buttermilk, 60g yogurt, 10ml vanilla, and 5ml vinegar. Whisk until the mixture looks like a thick, creamy pale yellow liquid.
  4. Add the 2 tsp purple gel coloring to the wet ingredients and whisk until vibrant.
  5. Make a well in the dry ingredients and pour in the purple liquid. Using a spatula, fold gently from the bottom up until no streaks of white flour remain.
  6. Divide the batter evenly between the prepared pans and bake for 30 to 35 minutes until a toothpick inserted in the center comes out clean or with a few moist crumbs.
  7. Let the cakes cool in the pans for 10 minutes before transferring to a wire rack.
  8. Beat 225g softened cream cheese and 115g butter until smooth and airy. Gradually add 300g sifted powdered sugar, 5ml vanilla bean paste, and 2ml lemon juice. Whip on high for 2 minutes until it looks like a silky white cloud.
  9. Once completely cold, use a serrated knife to trim any domed tops. Place one layer on a plate, spread a thick layer of frosting, and top with the second layer. Coat the exterior in a thin crumb coat and chill for 20 minutes before the final frost. Apply the remaining frosting in swoops and swirls.