First off — why clean the toaster? Safety, for one. Crumbs left inside can be hazardous, especially if they get burnt. It’s the same with oil or grease that leaks out onto the tray and other components. Leftover food could also attract unwelcome animal guests, which track germs and bacteria inside.
Proper appliance maintenance also goes a long way to your appliance’s longevity. Keeping your toaster clean, and therefore functional, means it’ll serve you a longer time. And that way your little gadget friend can keep turning out perfect crunchy cheese sandwiches to your heart’s content.
If you have the pop-out variety, or use the toaster oven for just bread, a quick clean once a week should suffice. But if you use the toaster oven to heat up larger or messier food — particularly if there’s plenty of oil, sauce, or butter involved — you may have to clean it immediately after use.