Snicker's Peanut Butter Cake

1 devil's food cake mix
1 cup peanut butter
3 snicker's bars
1 1/4 cups water
1/2 cup oil
3 eggs
1 can chocolate icing
marshmallows

Preheat oven to 350�F. Mix cake mix, peanut butter, water, oil and eggs and one Snickers bar, cut up into slivers. Pour into a 13-by-9-inch greased pan. Bake cake for 35 minutes. Take out and let it cool for 5 minutes. Spread the icing evenly over the cake. Cut the two remaining Snickers bars into approximately 1/2-inch pieces. Decorated the top of the cake with the pieces.