Chocolate Cake not for the Faint of Heart

I can't wait to make this for our friend's birthday this week. I made it once before for another birthday and realize that special occasions really should be the only time to pull out this cake for so many reasons. It's quite possibly just super amazing and maybe the best chocolate cake I've ever had.

"dry mixture"
2 cups flour
2 cups sugar
1 tsp baking soda
pinch of salt

"wet" mixture
2 sticks butter
1 cup water
1/3 cup cocoa


3/4 cup sour cream
2 eggs
1 tsp vanilla

Whisk flour, sugar, baking soda and salt together (dry mixture).  In a saucepan bring butter, water and cocoa to a boil (wet mixture).  Add the two mixtures and mix well.  Add sour cream, eggs and vanilla.  Pour into a 9x13 pan and bake at 350 degrees for 35 minutes, or until toothpick comes out clean.

Frosting
 1 stick butter
1/3 cup + 1 Tbsp milk
1/4 cup cocoa
4 1/3 cups powdered sugar
1 tsp vanilla

In a saucepan, bring butter, milk and cocoa to a boil.  Then add powdered sugar and vanilla.  Pour over warm cake and serve.