The easy answer is always Totino's pizza rolls or a Hot Pocket, which @Mog 's food guide pyramid is built upon.
However, aside from melting cheese on some nacho chips, and then putting salsa on it when it comes out of the microwave, I'm gonna have to go with these bad boys from Sam's Club:
However, aside from melting cheese on some nacho chips, and then putting salsa on it when it comes out of the microwave, I'm gonna have to go with these bad boys from Sam's Club: