It is a bet. What you do, is you go to a restaurant with your friends and order food. Then, you switch your order with one of your friends. You each place a random object in the other persons food, and then return it to the original owner. They must eat it without knowing what you put in it. Then you guess on what they put in your food, and each person submits a predetermined amount of money into a pot. The closest guess is the winner.
dude, lets go to Burger King and do some mumching!