Mix a box of yellow or white cake mix according to directions. Bake in a 9x13-inch pan. When done, remove and frost with the following frosting.

ICING:

1 (5 oz.) can evaporated milk
1 c. sugar
1/2 c. butter
1 tbsp. vanilla

Mix milk, sugar and butter over medium heat; cook until it comes to a bubbly boil. Add peanut butter and vanilla; beat well. Frost cake.