Easy Red Velvet Cake
["1 box Duncan Hines butter cake mix", "1 c. buttermilk", "1 stick margarine", "1 tsp. soda", "3 eggs", "1 tsp. cocoa", "1 tsp. vanilla", "1 bottle red cake color", "1 Tbsp. vinegar"]
["Mix cake mix with cocoa.", "Add vanilla, buttermilk, cake coloring, margarine and eggs.", "Blend until moistened.", "Add soda and vinegar and mix into cake mixture.", "Beat for 4 minutes at medium speed.", "Bake at 375\u00b0 in layer pans for 25 to 30 minutes. Frost with Cream Cheese Frosting."]
["cake mix", "buttermilk", "margarine", "soda", "eggs", "cocoa", "vanilla", "red cake", "vinegar"]