Preheat oven at 360°F (175 degrees C). Grease muffin pans or line with paper cups.
In a large bowl, beat together butter and sugar until with an electric mixer until light and fluffy. Mix in the eggs, buttermilk, red food coloring and vanilla. Stir in the baking soda and vinegar.
Combine the cocoa powder and salt. Stir into the butter just until blended.
Spoon the butter into the prepared cups. Do not overfill since the mixture will rise.
Bake in the preheated oven 20-25 minutes or until the toothpick inserted comes out clean.
Cool in the pan or in a wire rack then frost with Cream Cheese Frosting.
1/2 cup butter1 1/2 cup white sugar2 eggs1 cup buttermilk1 tbsp red coloring1 tsp vanilla extract1 tbsp distilled white vinegar1 1/2 tsp baking soda2 cup cups all purpose flour1/3 cup unsweetened cocoa powder1 tsp salt