Preheat oven to 350°F. Prepare 3 (9-inch round) baking pans by lightly coating with oil and dusting with flour.

Cream together butter and sugar. Add cocoa, baking soda and House-Autry Buttermilk Biscuit Mix; mix well. Add buttermilk; mix well. Add eggs one at a time until well incorporated. Add red food coloring, vinegar and vanilla; mix well. Pour into prepared pans. Bake for 30 minutes, or until a toothpick inserted in the center of the layers comes out clean. Remove layers from oven. Remove from pans and cool completely on a baking rack.

Marshmallow Cream Cheese Frosting: In a mixer, combine marshmallow cream, cheese, butter and sugar at low speed until well blended. Scrape down sides and increase speed to high; mix until fluffy. Reduce speed back to low and add vanilla extract. Thin with buttermilk, if necessary. Cut each cake layer in half and frost; making 6 layers total. Cover outer edges with chopped pecans.