Reheat left over pizza on a cast iron skillet, just trust me here . Used to do a thing when making a sandwich where’d I’d make two. Second one got those stacker pickles added, wrap in tin foil and leave in fridge overnight. Real good. I can’t do the ‘warm up your coffee’ in the microwave if it goes cold. Nope, fresh cup a must. As far as cereal I remember Corn Pops and lucky charms were just nasty if they sat too long. Actually stank up the kitchen.