Texas Sheet Cake

My mom made this for me tonight. It was soooo good, and FAST! If you need to entertain some friends quickly it comes together fast and is delicious!!! ** I have an announcement to make! I almost posted the Pioneer Woman recipe because I thought it was better than this one. . .Turns, out, they are almost EXACTLY THE SAME! (Leave it to my mom to make an amazing Texas sheet cake. I just hadn't made it in forever!) The only difference is Ree uses all butter. . . of course.

Cake:

2 cups flour, sifted
2 cups sugar
1/2 cup margarine
1/2 cup shortening* Lindsey's notes: I made a pioneer woman recipe of this and it was all butter. It was great! :) Of course.
1/4 cup cocoa
1 cup water
1/2 cup buttermilk
2 eggs, slightly beaten
1 teaspoon cinnamon
1 teaspoon vanilla
1/4 teaspoon salt
1 teaspoon soda


Frosting:

1/2 cup butter
1/3 cup milk
1/4 cup cocoa
1 package (16 oz.) powdered sugar
1 teaspoon vanilla
1 cup nuts, chopped

Mix flour and sugar. Set aside. Stirring constantly, bring margarine, shortening, cocoa and water to a boil. Pour over flour mixture. In another bowl, mix buttermilk, eggs, soda, cinnamon, vanilla and salt. Stir into hot mixture. Pour into an 11" x 16" pan. Bake at 400 degrees for 20 minutes. To make frosting, stir and bring margarine, cocoa and milk to a boil. Stir in powdered sugar, vanilla and chopped nuts. Cool slightly. Frost warm cake.