David, I think that this may be what you are looking for...

PUPPY CHOW

Melt together:
1 stick (1/2 cup) margarine
1 cup chocolate chips

Stir in and mix well:
1/2 cup peanut butter
1 tsp. vanilla

Pour over and mix to coat thoroughly:
6 cups rice chex cereal
peanuts (optional, but good)

Pour 2 cups powered sugar into a large bag and then add the chex mixture. Shake the bag until the mixture is dusted and coated with the powdered sugar.