Preheat oven to 325° with rack in center. Line bottom of 9-inch round or square cake pan with parchment paper cut to fit, and spray sides and bottom with nonstick cooking spray. If making tall cupcakes, line standard muffin pan with standard cupcake liners for regular cupcakes, or jumbo cupcake liners for tall cupcakes, and spray cupcake liners. Set aside.
Whisk together cocoa powder and Vanilla Cake Mix in a bowl. Set aside.
Using a stand mixer with paddle attachment, or mixing by hand, mix together eggs, oil, vanilla, and buttermilk. Add food coloring and vinegar and mix again. Slowly add Vanilla Cake Mix and stir until it is just evenly blended. Do not overmix.
Pour batter into prepared cake pan, or fill standard cupcake liners two-thirds full, or fill jumbo liners up to the top of the metal cups of the muffin pan. Bake until center springs back when touched and toothpick inserted near center comes out clean, 54 to 60 minutes for cake, 20 to 23 minutes for regular size cupcakes, or 24 to 29 minutes for tall cupcakes. Do not overbake.
Cool pans on rack. Let cool 15 to 20 minutes before removing from pan. To remove cake from pan, first run a knife around the edge, then turn out cake onto a serving plate, and peel parchment paper off bottom. Do not frost until completely cool. Frost with Cream Cheese Frosting for a traditional taste.
Best eaten fresh, not frozen.
© Pamela's Products, Inc.