Texas Sheet Cake

Preheat oven to 400 degrees.
Grease and lightly flour a 15x10 inch jellyroll pan. Set aside.
Sift together sugar and flour in a large bowl; set aside.
2 cups sugar, 2 cups all-purpose flour
Combine butter, shortening, cocoa, and water in a medium saucepan over medium-high heat. Bring to a boil, stirring constantly, until butter and shortening melt.
½ cup butter or margarine, ½ cup shortening, ¼ cup unsweetened cocoa, 1 cup water
Remove from heat and pour over sugar and flour mixture, stirring until dissolved. Cool slightly.
Stir in eggs, buttermilk, baking soda, and vanilla. Mix well.
2 large eggs, ½ cup buttermilk, 1 teaspoon baking soda, 1 teaspoon vanilla
Pour into the prepared jellyroll pan.
Bake at 400 F for 20 minutes.
Start making the icing when the cake has about 10 minutes left to bake.

Combine butter, cocoa and milk in a medium saucepan.
½ cup butter or margarine, ¼ cup unsweetened cocoa, ⅓ cup milk
Cook over low heat 5 minutes or until margarine melts.
Then turn the heat up to medium and bring to a boil.
Remove from heat and stir in sugar and vanilla.
16 ounces powdered sugar, 1 teaspoon vanilla
Beat at medium speed with an electric mixer until smooth and the sugar dissolves.
Stir in pecans. Mix well.
1 cup chopped pecans
Pour and spread icing over the top of the sheet cake.