Texas Sheetcake

Grease a 9x13 pan. Can be doubled if you want to make a cookie sheet size. 

Sift dry ingredients together in a large bowl:
2 c. flour
2 c. sugar
1 tsp baking soda
1/4 tsp salt

1 c. butter
1/3 c. unsweetened cocoa powder (not Dutch-process)
1 c. water
2 eggs
1/2 c. buttermilk
1 1/2 tsp vanilla

In a saucepan combine butter, cocoa, and 1 cup of water. Bring mixture just to boiling, stirring constantly. Remove from heat. Add the cocoa mixture to the flour mixture and beat with an electric mixture on medium to high speed until thoroughly combined. Add eggs, buttermilk, and vanilla. Beat for 1 minute (batter will be thin). Pour batter into the prepared pan.

Bake at 350 for about 35 minutes until a wooden toothpick comes out clean. Remove pan from oven, and immediately make the frosting. It gets poured on hot.

Frosting:
In a medium saucepan combine 1/4 c. butter, 3 Tbsp unsweetened cocoa powder, and 3 Tbsp buttermilk. Bring to boiling. Remove from heat. Stir in 2 1/4 cups of powdered sugar and 1/2 tsp vanilla. Beat until smooth with your hand and immediately spread over cake.