Preheat oven to 350 degrees. Spray two 8-inch layer pans with non-stick spray.
In a bowl, cream together butter and sugar until light and fluffy. Add eggs one at a time, beating well after each one. Add vanilla.
Sift flour, cocoa, and baking soda together. In a separate bowl, combine buttermilk, vinegar, red food coloring, and hot water.
Add dry ingredients alternately with buttermilk mixture. Blend well. Pour batter into prepared pans. Bake for 25 minutes or until cake tests done with a toothpick.
Cool completely and frost with cooked white frosting.
