Mrs. Elkins' Sheath Cake
["2 c. sugar", "2 c. sifted flour", "1 stick margarine", "1/2 c. vegetable oil", "4 Tbsp. cocoa", "1 c. water", "1/2 c. buttermilk", "2 eggs", "1 tsp. baking soda", "1 tsp. cinnamon", "1 tsp. vanilla"]
["Sift sugar and flour into a large bowl.", "In saucepan, bring next 4 ingredients to rapid boil. Stir into sugar and flour.", "Mix in other ingredients.", "Pour into greased 11 x 16-inch pan.", "Bake at 400\u00b0 for 20 minutes.", "Five minutes before done, make icing."]
["sugar", "flour", "margarine", "vegetable oil", "cocoa", "water", "buttermilk", "eggs", "baking soda", "cinnamon", "vanilla"]