Ingredients
6 large eggs, separated
1 1/2 cups sugar
2 cups whole milk
1 teaspoon pure vanilla extract
6 cups (12 sticks) unsalted butter, softened
1/2 cup (about 3 cups whole berries) blackberry puree
Preparation
Follow instructions for Vanilla Buttercream, adding 1/2 cup blackberry puree (about 3 cups whole berries) in step 5.
