Bring to boil; remove from heat:

2 sticks butter
1 c. water
4 tbsp. cocoa

Add:

2 c. flour
2 c. sugar
1/2 tsp. salt

Mix well.

Beat in:

2 eggs
1 tsp. baking soda
1/2 c. sour cream

Mix until well blended. Pour into LARGE greased cookie sheet. Bake at 375 degrees for 20 minutes.

FROSTING FOR SHEET CAKE:

Bring to boil and remove from heat:

1 stick butter
4 tbsp. cocoa
6 tbsp. milk

Add to above and stir with spoon:

3/4 box powdered sugar
1 tsp. vanilla
1 c. chopped walnuts

Frost cake while hot.