2 sticks butter
1/4 c. cocoa
1 c. water
1/2 c. buttermilk
2 eggs, beaten
2 c. sugar
2 c. plain flour
1 tsp. baking soda
1 tsp. vanilla

Mix the first 5 ingredients in a saucepan and bring to a boil over medium heat. Pour boiling mixture over the 4 remaining ingredients. Mix well in mixing bowl. Place in a 9 x 13-inch greased and floured pan. Bake for 35 minutes at 350 degrees. Let cake cool completely.

FILLING:

3/4 c. peanut butter
1 tbsp. cooking oil

Mix these and spread over cool cake.

ICING:

1 stick butter
1/4 c. cocoa
6 tbsp. buttermilk
1 box confectioners sugar
1 tsp. vanilla

Mix the first 3 ingredients and bring to a boil over medium heat. Pour boiling mixture over remaining ingredients. Mix well in mixing bowl. Spread icing over filling already on the cake.