No bag. No butter or oil. Nothing to throw away afterward. And even no un-popped kernels. Take 1/4 cup of dry popcorn kernels and place in the bottom of a microwave-safe glass bowl (pyrex is a great choice). Place a microwave-safe plate on top of the bowl. Plate should be wide enough to go beyond the rim of the bowl. Microwave for 2 minutes 45 seconds. Watch in glory as your popcorn pops perfectly into little puffs of heaven.