Come to find out this a Great Lake region (what some might call the mid-west, but really let's call it what it is) pot-luck staple. It's big, like the size of Texas, or Lake Superior, hence the name. It's not like it makes more than 12 or 16 servings, like any other cake, it doesn't have big volume, but it's flat and it takes up space on the counter! It is super moist and very cocoay.

Ingredients

1 cup melted butter

1 cup water

0.25 cup cocoa powder

2 cups sugar

2 cups flour

0.5 teaspoon salt

1 teaspoon baking soda

2 eggs

0.5 cup sour cream

1 teaspoon vanilla

Frosting

0.5 cup melted butter

0.25 cup cocoa

6 tablespoons milk

1 teaspoon vanilla

1 pound powdered sugar

Oven 350 degrees. 

On a pot on the stove, melt the butter, add the water and cocoa. Bring to a simmer. Off the heat. In a bowl combine the sugar, flour, salt, and soda. Mix briefly. Add the cocoa mixture. Combine. Add the sour cream, eggs, and vanilla. Pour into a well oiled, (but don't line the pan with parchment) 11x16 or 12x17 or half sheet pan or jelly roll pan- a pan bigger than 9x11 and bake 20 minutes. 

In the last minutes of baking start the frosting because you pour it onto a hot cake. 

Melt the butter, add the milk, vanilla, and powdered sugar. Pour over the hot cake. Spread evenly. Cool and serve.