One of all-time favorites.
Here’s what you need.
Plus some water, that didn’t make it into the picture. 
Combine the butter, water, and cocoa in a medium sized pot. 
Bring them to a boil.
Pour the boiling mixture over the pre-mixed flour and sugar, and stir to combine.
Add the remaining ingredients: buttermilk, eggs, baking soda, salt, and vanilla. 
Pour into a greased jelly roll pan. 
Bake at 400° for 20 minutes.
Once you remove the cake from the oven start the frosting.
Bring butter, buttermilk, and cocoa to a boil in the same pot used earlier. (You don’t even need to wash it between uses!)
Once boiling pour over powdered sugar in a mixing bowl, add vanilla and beat til smooth.
Immediately pour the hot frosting over the brownies. It will run and cover the cake with little help from spreading. Let cool before serving. 
Who can resist a face like this?
“May I have some more, please?”
Ingredients
- Cake: 1 cup butter (2 cubes)
- 1/4 cup cocoa
- 1 cup water
- 2 cups flour
- 2 cups sugar
- 1/2 cup buttermilk
- 2 eggs
- 1 tsp baking soda
- 1/4 tsp salt
- 1 tsp vanilla
- Frosting:
- 1/2 cup butter (1 cube)
- 1/4 cup cocoa
- 1/3 cup buttermilk
- 16 oz powdered sugar (2 lbs)
- 1 tsp vanilla
Instructions
- Cake: Bring butter, water and cocoa to a boil in a medium sized pot, on medium heat.
- In a mixing bowl combine the flour and sugar. Add the hot butter mixture to the mixing bowl and stir to combine. Add the remaining ingredients and mix well. Pour into a greased jelly roll pan (11 inch x 16 inch) and bake at 400° for 20 minutes. Remove from oven and make frosting.
- Frosting: Bring butter, cocoa, and buttermilk to a boil in the same pot used before for cake. Once boiling add the powdered sugar and vanilla and beat til combined and smooth. Frost the cake while the frosting is hot. Let cool before serving.
