The idea that any food can taste better by adding either cheese OR marshmallow.
Yet to be disproved, however the Cheese-Marshmallow Theory is unlikely to become a law due to the fact that it can never be proven.
Julian: I got it! Cereal...
John: Marshmallows...Lucky Charms man. Trust me, I was a non-believer at first too but you'll come around. The Cheese-Marshmallow Theory can not be disproved!