Cake:

1 stick butter
1/2 c. oil
4 tbsp. cocoa
1 c. water
2 c. sifted flour
2 c. sugar
1/2 c. buttermilk
2 eggs
1 tsp. baking soda
1 tsp. vanilla

Put butter, oil, cocoa and water in saucepan and bring to a boil. Sift together flour and sugar and add the chocolate mixture. Then add the buttermilk, eggs, baking soda and vanilla. Mix well. Pour into a jelly roll pan.

Bake at 400°F for 20 minutes. Cool.

Frosting:

1 stick butter
4 tbsp. cocoa
1/3 c. buttermilk
1 lb. confectioners sugar
1/2 tsp. salt
1 tsp. vanilla
1 c. walnuts, chopped

In a saucepan, bring butter, cocoa, and buttermilk to a boil. Remove from heat and add remaining ingredients.

Mix well and frost cake. Cut into squares.