Seasoning is a layer of fat or oil that is baked onto the iron to protect it and aid in its non-stick properties. The bare iron is coated with oil both inside and out, and when heated, the oil goes through a chemical change called polymerization, transforming the liquid oil into a hard shell. This layer of seasoning is surprisingly durable. Despite its name, seasoning does not affect the taste of your food. There are some who insist that the seasoning holds flavor, and the taste of past meals will find its way into whatever you’re currently cooking. This is not only hard to believe, but also pretty gross, and we’ve found little evidence to support it. Seasoning will build up over time as additional oils get cooked into the iron, but you shouldn’t be able to taste yesterday’s pork chops in tonight’s hash browns, assuming you cleaned your skillet properly. Related note: seasoning is both a noun and a verb. The noun refers to the layer of polymerized oil; the verb refers to the process of applying this oil.