Cast Iron – Benefits, Seasoning, Cleaning

Sometimes, I’m surprised at people’s ideas about cast iron. There’s a perception that it’s difficult to care for or maintain, or that it’s a fragile, finicky form of cookware. Nothing could be further from the truth.

Cast iron is, in almost every respect, a miracle-product. In this post, I’ll tell you all about why cast iron is wonderful and you should use it.

Benefits of Using Cast Iron

  1. It conducts heat very well, and because of its mass, it also conducts heat very evenly. In short, it is excellent cookware. Cast iron tends not to form hot-spots, meaning that slow-cooked chili or beans are less likely to burn on the bottom of the pot. The high thermal mass of cast iron means that it tends to stay the same temperature as opposed to fluctuating quickly. This is helpful on an electric stove, where the heat source is not constant, but alternates between on and off periodically.
  2. It is remarkably cheap. A cast iron skillet can be had for between $15 and $30 depending on the size. Compared to thin  steel or aluminum pans at the same price, cast iron cooks ten times better. Larger cast iron pieces like dutch ovens can be more expensive, but their cost may be justified by the next point.
  3. It is nearly indestructible. If need be, you can take sandpaper or a buffing wheel to it, although that is hardly ever necessary. As a last resort, cast iron can be left in the oven while a clean cycle is run. This cooks off everything on the metal, essentially resetting it to “new”. As long as cast iron isn’t broken into pieces and has no holes in it, it’s salvageable.
  4. It is incredibly versatile. You can use cast iron on the campfire or the grill just as easily as you can on a stove. In a pinch, you can flip a cast iron skillet upside down and use its bottom as a griddle for making pancakes. It can even be used as a quick-thaw device.
  5. It doesn’t have the potential to leach harmful chemicals into your food, like Teflon does. In fact, cooking with cast iron is rumored to add to your dietary iron intake (although it’s questionable whether it’s a significant amount).

Cons to Using Cast Iron

All that being said, there are some down-sides to cast iron.

  1. It’s heavy. This is an issue for people who don’t have the hand and arm strength to handle the cookware comfortably.
  2. It requires some minor maintenance (seasoning).
  3. Cleaning it is not as easy as some types of cookware.

Seasoning Cast Iron

Seasoning cast iron is the process of building up a layer of carbonized fat and protein on the surface. This serves two purposes: it keeps the metal from rusting and it makes food less likely to stick to the pan.

There are a variety of methods out there on how best to season cast iron. All of them involve coating the cookware with fat, like lard, shortening, or vegetable oil, and then heating it. The fat is sometimes reapplied during the process. The main variance in the recipes seems to be the temperature at which the cast iron is seasoned. My philosophy is that the goal of seasoning is to build up a carbonized layer of fat, so if your oil isn’t smoking, you’re not doing it right. I like to season cast iron on the grill, because it’s more than capable of putting out a lot of heat and all the smoke produced stays outside the house. I coat the cookware in shortening or vegetable oil and then set it over the grill until it starts smoking. After it’s smoked for a while and much of the oil has burned off, I put on another thin coat. I keep repeating this until there is a smooth, black layer of carbonized fat on the pan. If you’ve ever tried to clean off drippings that have cooked onto a roasting pan or something like that, you know how slick and hard to get off they are. That’s what you’re trying to cover your pan in.

Once the pan is seasoned, it requires regular maintenance. This is easy to build into your cooking and cleaning process, so it shouldn’t be too onerous. If you simply cook in the pan without maintaining it, the seasoning will gradually wear off. The most prominent symptom of this is that food will stick to the pan like crazy and it will be very difficult to clean. One step in maintaining the pan is to always wipe the pan down with a thin layer of oil or shortening after you use it. The pan should still be warm when you do this. If you do a lot of greasy cooking, the pan may get enough fat from the cooking process to skip this step, but I think that most modern cooks don’t do that much greasy cooking. It’s said that cooking a mess of bacon in a pan is one of the best ways to give its seasoning a kick.

Cleaning Cast Iron

I have found that properly cleaning the pan is a key component of maintaining the seasoning. Before I settled on my current cleaning routine, I could not keep may pans seasoned, and I have to admit that I questioned the truth of the legendary “cast-iron non-stick seasoning.” What I have found to work is the following:

  • I never use soap to clean the cast iron.
  • I never use water to clean the cast iron.
  • I never use a metal scouring pad or metal scrub-brush to clean the cast iron.

Well, at this point, you are probably wondering how I clean the cast iron, if I don’t use soap or water. The answer is salt. Not table salt, though. Kosher salt.

The  image above shows the two types of salt: table salt on the left and Kosher salt on the right. The Kosher salt has much larger grains, which makes it perfect for scouring a cast iron pan. When I’m done cooking, I pour a liberal sprinkling of Kosher salt into the pan and then use a towel to scour the pan well. Sometimes it also works well to scrape the salt around with the end of a wooden spatula. A wooden spatula is okay because the wood is soft enough that it won’t take off the seasoning.

In the beginning, before I built up a good seasoning, I had quite a bit of work to do, scouring out the pans, but now that my seasoning is good, cleanup is relatively easy. I find that the salt is not only an excellent scouring medium, but it also absorbs a lot of the grease that might be left over in the pan. It absorbs a lot of grease, but not all of it, which means that there is often a light coating of grease left when I’m done cleaning, and I don’t have to wipe down the pan with any additional oil.

One note: the dishrag that you use to scour the cast iron will instantly be permanently stained and will also become a bit stiff and greasy. I like to dedicate one or two rags to that purpose, so that I don’t ruin all of my dishrags.

I have heard it said that the best cast iron seasoning can be “as non-stick as Teflon.” I, personally, have never seen anything as non-stick as Teflon, and when I want to make a perfect fried egg or an omelet, I turn to Teflon. Additionally, no matter how easy my cast iron has become to clean, it’s nothing close to the “one-wipe with a towel” of my Teflon pan.

That being said, what makes  cooking with cast iron worth it to me is the feeling that I’m working with an almost-living piece of cookware. There’s just something so satisfying about hanging the pan up on the rack, gleaming, black, and clean. Although I’m romanticizing it a bit, it’s almost as if the pan is storing up the memories of the meals I’ve cooked in it.

Issa’s Note: Check out Lodge cast iron on Amazon.