The most crucial part of cast iron care is seasoning, which involves glazing the pan with a layer of oil to protect its surface and keep food from sticking. Some cast iron brands come pre-seasoned, while other pans require you to do it yourself, but every cast iron pan occasionally needs re-seasoning to maintain its coating.

Even if you care for your cast iron pans, regular wear and tear will take its toll, and re-seasoning can bring it back to a nearly-new condition. Food & Wine notes that you only need to re-season about two times per year, and if you’re not sure if your pan is due for some upkeep, cook an egg in it; if the egg sticks, it’s probably time to re-season.

To re-season your cast iron, apply a thin layer of oil to the cleaned-out pan, then put it in the oven at 400 degrees F for an hour. NYT’s Wirecutter notes that you should use neutral oils with a high smoke point, like vegetable or canola; olive oil should be avoided because it breaks down at a lower temp and can impart an unpleasant flavor.