Generally, you can use all the same things in an air fryer that you would use in a regular oven, including aluminum foil, parchment paper, and any oven-safe cookware. However, you should never put plastic containers and cardboard in your oven or air fryer. There are also a few foods that aren’t meant to be put in an air fryer. Specifically, anything wet, like fry batter or meltable cheese, will get caught in your fryer’s fans.