Cast iron seasoning is a Goldilocks situation. You shouldn’t cook in an unseasoned skillet, and yet you can season your skillet too much.
Cast iron skillets are sturdy, durable, and have an unmatched ability to retain and distribute heat. This makes them the cookware of choice for searing steaks, sautéing mushrooms, and shallow-frying chops or butterflied filets.
With prudent use and proper care, these heavy-bottomed and thick-walled cooking vessels will serve dutifully as your kitchen workhorses for a lifetime. Some even become heirlooms and get passed down from one family cook to another through generations.
True as it may be, many cooks shy away from the idea of owning cast iron cooking vessels because they find the associated rituals of cast iron care to be intimidating.
While cast iron care is no rocket science, it does take a while to learn, and there’s lots of conflicting information out there on the Internet (written by folks who’ve never owned or seldom cook with cast iron).
As a food magazine that encourages you, our readers, to reach out and ask questions, we’ve found seasoning to be the biggest concern among future and novice cast iron cookware owners alike.
Can You Season a Cast Iron Skillet Too Much?
All cast iron pans must be seasoned, or they will corrode and rust.
However, when it comes to seasoning cast iron, you can have too much of a good thing. There is such a thing as over-seasoning your pan, and an over-seasoned pan requires your prompt attention.
In this article, we will discuss the finer points of this process to figure out how much is too much (and how much is enough).
To season a cast iron skillet, you must first strip off the old seasoning first. For a brand new pan, just soap it well and dry it thoroughly. For a used pan, you may need to spray the vessel with heavy-duty oven cleaner and let it work overnight as described by our fellow journalists at Cook’s Illustrated.
You season a cast iron skillet by rubbing a little oil all over—the cooking surface, bottom, sides, and handle—then baking the skillet, upside down, in a hot oven for an hour.
As a result, the oil polymerizes onto the metal and forms a patina that protects it from corrosion and rust (and, as a side benefit, keeps foods from sticking).
Once the skillet has cooled down, which usually takes an hour or two, it is ready for you to use. Unless you made a mistake somewhere in your seasoning, the frying surface will have an even black color, without gray spots or black flakes.
Else, you need to strip the seasoning off and repeat the process.
How Much Oil to Use for Seasoning Cast Iron
Through trial and error, we’ve concluded that a ¼ teaspoon of oil for the cooking surface and another ¼ teaspoon for the bottom, sides, and handles are more than sufficient to season a 10.25-inch cast iron skillet.
Smaller skillets will use up slightly less oil; bigger skillets slightly more.
In any case, the fact of the matter is that you rarely need more than a teaspoon of cooking oil. You should aim to use as little cooking oil as possible. Add too much, and it will pool in the pan and not polymerize evenly, resulting in a flaking seasoning.
The best oil for seasoning cast iron is flaxseed oil, as it’s capable of forming strong molecular bonds with the iron. The best temperature is as high as your oven goes, whether that’s 450°F (230°C), 500°F (260°C), or higher.
Apply the oil to the surface with a paper towel or clean cloth in a circular motion. It is important that you leave a very thin layer of oil on the bare iron and wipe off the excess before baking the pan.
Even if the pan is turned upside down to prevent pooling as it should, using too much oil will not be enough to limit the damage.
Keeping Your Pan Well-Seasoned
For the first week or two after seasoning your pan, use it to prepare fatty foods that build up the seasoning. My go-to meats for the purpose are thick-cut steak, pork chops, hearty sausages, and bacon strips. Caramelized onions, French fries, and shallow-fried potato latkes do wonders.
To keep your cast iron skillet in mint condition, use plenty of fat, butter, or cooking oil, and do not cook acidic foods in it.
The acid will react with the metal, stripping the seasoning off and causing the cooking vessel to leach dietary iron into your home-cooked meals. This means that recipes that use wine, vinegar, and tomatoes are out of the question, especially if they need to be simmered for a long time.