• 2 1/2 cups cake flour, sifted
• 1 cup (evaporated cane juice or plain white) sugar (use 1 1/2 cups if you're using food coloring instead of beet juice - see below)
• 2 tablespoons unsweetened, unprocessed light cocoa powder
• 1 teaspoon baking powder
• Red liquid or gel food coloring (see Notes about beet juice)
• 1/2 cup unsalted butter
• 1 teaspoon vanilla extract
• 1 teaspoon white vinegar