Texas Sheet Cake
["2 sticks margarine", "1 c. water", "4 Tbsp. cocoa", "2 c. sugar", "2 c. self-rising flour", "1 c. sour cream", "1 tsp. vanilla"]
["Bring margarine, water and cocoa to a boil in heavy saucepan over medium heat, stirring well.", "Remove from heat and add remaining ingredients.", "Mix well and pour into a well-greased and floured jelly roll pan (15 1/2 x 10 1/2 x 1-inch).", "Bake at 350\u00b0 in a preheated oven for 30 minutes.", "Ice with the following frosting."]
["margarine", "water", "cocoa", "sugar", "flour", "sour cream", "vanilla"]