Chinese Rice Bowl Magic - Appearing Water!

The performer shows two empty bowls. One of these bowls is filled to the brim with rice and covered with the other. When uncovered when uncovered the rice has magically doubled in I quantity over flowing the bowl. The rice is now emptied out and the empty bowls are placed together again. When separated the bowls are found to be filled with water, which is poured from bowl to bowl, apparently increasing in quantity as it is poured.

Rice can also be substituted for puff rice. Please supply your own.