Source is my mom. I have no idea where she got this recipe but she's had it for 20-30 years if not longer. One of Anthony's coworkers is going to go to school in Seattle and his going away party is today. I was told there would be BBQ food so I thought this dessert goes with a southern theme of food : ) and it feeds tons of people Texas Sheet Cake 2 cups flour 2 cups sugar 2 sticks margarine 6 tablespoons cocoa 1 cup water 1 teaspoon baking soda 1/2 cup buttermilk 1/2 teaspoon salt 1/2 teaspoon cinnamon 1/2 teaspoon vanilla 2 eggs Sift together flour and sugar together in a large mixing bowl. In a small pan, combine margarine, cocoa, and water. Bring to a rapid boil. Then pour over flour and sugar. Mix well. Combine buttermilk and baking soda in measuring cup. Lightly beat eggs. Add buttermilk-soda and eggs to mixing bowl. Mix well. Add salt, cinnamon, and vanilla. Mix well. Pour into a greased and loured 16 X 11 X 1 inch jellyroll pan. Bake 20 minutes in a prehe...