Preheat the oven to (350°F) = (176°C) degrees. Grease the pan of choice below. Combine the dry ingredients flour and sugar in a bowl. Bring the butter, cocoa, and water to a boil. Turn the stove off. Add the buttermilk, baking soda, salt, eggs, and vanilla extract to the pan with the boiling mixture. Use a hand mixer or electric mixer to combine the flour and sugar in the pan, blend until smooth. Pour into a greased sheet cake pan.
Baking time: jelly roll/cookie sheet, 20-25 minutes (when a toothpick comes out clean)
Baking time: 9-inch by 13-inch pan, 35-40 minutes (when a toothpick comes out clean)
Grab a medium saucepan and melt the butter, add the cocoa and the milk. Bring to a boil stir or whisk constantly, add the powdered sugar, vanilla extract, and nuts. I make this frosting while the cake is baking and then spread it on the semi-cooled cake.