density of the material is what makes cast iron so good at retaining a large amount of heat energy in a small amount of volume. Innovations like helper handles help, but smaller cooks will probably struggle with tasks like flipping food or pouring a sauce from a cast-iron pan.
• It requires special cleaning . Because the cooking qualities of cast-iron cookware are dependent on how well seasoned it is, care must be taken while cleaning to prevent accidentally removing the layer of seasoning, or you’re gonna have to start from scratch.
All that said, there’s really not much to it when it comes to seasoning, maintaining, and storing your cast-iron cookware.
HOW TO SEASON AND
Modern cast iron is bumpy like that because it is not polished the way old cast iron was and retains some texture from the mold. I’ve compared my shiny, totally smooth 1930s Griswold pan (acquired at a flea market) to my ten-year-old Lodge skillet (which I bought new and seasoned myself) and found slight advantages with the old pan, but the new one does just fine.
So the key is all in seasoning it properly. How does it work?
Well, if you look at the surface of a cast-iron pan under a microscope, you’ll see all kinds of tiny pores, cracks, and irregularities. When you cook food in the pan, it can seep into these cracks, causing it to stick. Not only that, but proteins can actually form chemical bonds with the metal as they come into contact with it. Ever have a piece of fish tear
in half as you try to turn it because it seems like it’s actually bonded with the pan? That’s because it has.
To prevent either of these things from happening, you need to fill in the little pores, as well as create a protective layer in the bottom of the pan to prevent proteins from coming into contact with it. Enter fat.
When fat is heated in the presence of metal and oxygen, it polymerizes. Or, to put it more simply, it forms a solid, plastic-like substance that coats the pan. The more times oil is heated in a pan, the thicker this coating gets, and the better the nonstick properties of the pan.
Here’s how to build up the initial layer of seasoning in your pan:
• Scrub the pan by pouring ½ cup kosher salt into it and rubbing it with a paper towel. This will scour out any dust and impurities that have collected in it. Then wash it thoroughly with hot, soapy water and dry thoroughly. If your oven has a self-cleaning cycle, one trip through with the pan left inside will demolish even the toughest cooked-on crud and give you a bare pan to start with.
• Oil your pan by rubbing every surface—including the handle and the bottom—with a paper towel soaked in a highly unsaturated fat like corn, vegetable, or canola oil.
Unsaturated fats are more reactive than saturated fats (like shortening, lard, or other animal-based fats), and thus polymerize better. It’s an old myth that bacon fat or lard makes the best seasoning agent, probably borne of the fact that those fats were very cheap back in cast-iron’s heyday.
• Heat your pan in a 450°F oven for 30 minutes (it will
smoke), or until its surface is distinctly blacker than when you started. An oven will heat the pan more evenly than a burner will, leading to a better initial layer of seasoning.
• Repeat the oiling and heating steps three to four times, until the pan is nearly pitch-black. Pull it out of the oven and place it on the stovetop to cool. Your pan is now seasoned and ready to go.
Until you’ve got a good layer of seasoning built up, avoid using too much soap or cooking acidic sauces, as both can make the seasoning process take longer.
Maintenance
Many people are irrationally afraid of caring for cast iron.
The truth is, once you’ve got a good layer of seasoning, cast iron is pretty tough. You can’t scratch it with metal utensils.
You can’t destroy it by using soap (modern dish soaps are very gentle on everything except for grease). To maintain the seasoning and build on it, just remember a few key points:
• Use the pan often. A good layer of polymers should build up slowly in a succession of very thin layers. This means using your pan as much as possible—particularly for oil-based cooking such as frying or searing. Avoid making liquid-based dishes in the pan until it has acquired a reasonably good layer of seasoning.
• Clean the pan immediately after use. Removing food debris is much easier with a hot pan than one that has cooled. If you clean your cast-iron skillet while it is still
hot, chances are all you’ll need is a tiny bit of soap and a sponge.
• Avoid tough abrasives. These include metal scouring pads and cleaners like Comet or Bar Keepers Friend. The scrubby side of a sponge should be plenty for most tasks.
I’m particularly wary about this at dinner parties, when a well-intentioned guest may decide to chip in after the meal and get a little too generous with the elbow grease, scrubbing out some of my seasoning.
• Dry the pan thoroughly and oil it before storing . After rinsing the pan, set it on a burner and heat it until it dries and just starts to smoke, then rub the entire inside surface with a paper towel dipped lightly in oil. Take it off the heat and let it cool to room temperature. The oil will form a protective barrier, preventing it from coming into contact with moisture until its next use.
A good rub-down with oil prevents rusting.
Worst-Case Scenarios
There are basically only two really bad things that can happen to your cast-iron cookware, scaling and rust—and neither of them is that bad.
Scaling happens when you heat the pan too often without adding extra oil to it. Rather than coming off in microscopic bits, as the seasoning normally will, the layer of polymers sloughs off in large flakes. For the pan to reach this state, I
stored it in the oven for a month’s worth of heating cycles, without ever oiling the surface. It’s easy to avoid the problem by oiling the pan after each use and not overheating it (if you’re storing it in the oven, don’t leave it there during the cleaning cycle, for instance), but once it happens, there’s no turning back—you’ll have to reseason it from the start.
Rust can appear on a cast-iron pan that is not seasoned well enough and is left to air-dry. Unless the entire pan has rusted (in which case, you’ll have to reseason the whole thing), a rust spot is not much to worry about. Rinse out the pan, heat it until it dries and smokes, and rub it with oil.
After a few uses, the rusted spot should be perfectly seasoned again.
Which Pan Should I Buy?
If you’re lucky enough to come across a reasonably priced cast-iron pan (under $50 or so) from the early twentieth century at a yard sale or flea market, scoop it up immediately. You can also occasionally find good deals on eBay and sites like it.
I personally find it ridiculous to pay the $150-plus that some sellers are asking for old cast iron when a new cast-iron pan, like the 10¼-inch Seasoned Cast-Iron Skillet from Lodge costs a mere $16.98 and will give you an equally lustrous nonstick surface with just a bit of time and care.