2 c. flour
1 tsp. baking soda
2 c. sugar
1/2 tsp. salt
1/2 c. oil
1 1/2 sticks butter
1/2 c. peanut butter
1 c. water
2 eggs, beaten
1 tsp. vanilla
1/2 c. buttermilk

ICING:

1/2 c. evaporated milk
1 c. sugar
1 tbsp. butter
1/2 c. extra crunchy peanut butter
1/2 c. miniature marshmallows
1 tsp. vanilla

Mix together flour, sugar, soda and salt in 2-quart mixing bowl. Set aside.

In saucepan, bring oil, butter, peanut butter and water to a boil. Pour over dry ingredients and mix. Add beaten eggs, vanilla, and buttermilk, blending well. Pour batter into greased and floured 11x15x1 inch sheet cake pan. Bake 15 to 18 minutes in 350 degree oven.

While cake bakes, combine evaporated milk, sugar and butter in saucepan. Bring to boil, cook 2 minutes. Remove from heat and add peanut butter and marshmallows. Stir until melted. Stir in vanilla. Pour over warm cake and spread to cover.

NOTE: I sometimes use 14 1/2 x 10 1/2 x 2 inch pan.