Cast iron cookware is a funny animal: It’s versatile and super durable but it’s also particular and can all-too-easily turn into a rust-covered piece of garbage. And then, there are all these rules that come with cast iron pans, whispered things about seasoning and scrubbing with salt and the dangers of soap … it’s just a lot.
But don’t let its care put you off of cast iron entirely. It’s great stuff and you have me to help you figure out the care part of things. The good news is that, when it comes to the cleaning part at least, most of the old cast iron “rules” can be tossed out the window. Here are the things you really need to know about washing and storing a cast iron pan.
Conventional cast iron wisdom dictates that you must never, ever use dish soap to clean a cast iron pan. Lies! You may absolutely use dish soap to wash a cast-iron pan.
The idea behind the insistence on no-soap is that soap will erode the layer of oil-based seasoning that lends the pan its nonstick surface. But, because the oil is exposed to heat for a prolonged time, its chemistry changes and it becomes polymerized—which means that it no longer responds to soap the way unpolymerized oil does, and won’t break down from exposure to soap.
The real thing you need to protect your cast iron pan from is water—not soap! Damage is far more likely to occur because of exposure to water because cast iron will rust. Very fast. Shockingly fast. Alarmingly fast.
You should absolutely use water to wash cast iron pans BUT once the pan is clean, the best thing you can do for the longevity of your cast iron is to dry it off immediately. Cast iron, however, has a tendency to stain dish towels, so it’s worth investing in a set of dark towels if you regularly cook with, and therefore clean, cast iron cookware.
Never, ever leave a cast iron pan to soak in the sink.
Thorough drying is truly the best, best, best thing you can do for your cast iron, but if you can add one thing to your cast iron care routine on top of that, let it be this: After drying, pour a small amount of oil into the pan, rub it vigorously with a paper towel until the pan appears to be dry, and then set the pan over a medium flame for five minutes. That last step does two things; one, it will dry the pan out even more, and two, it will add a thin layer to the pan’s seasoning, which will help to protect it from rusting due to moisture in the air while it’s not in use.
Maybe, though, you’re curious about how to clean a cast-iron pan without the use of soap. Sure! Let’s cover that.
One of the most popular methods for cleaning cast iron is to use coarse kosher salt to scour the pan. Pour about a cup of the salt into the pan and use a dishrag (see how having that set of dark towels is starting to make more and more sense?!?) or paper towels to scrub away grease and bits of food. Rinse the pan well with warm water, dry it thoroughly, and re-season.
Salt can also be used if your cast-iron cookware does develop rust: The salt scrubbing method will scour away small bits of rust. Very fine steel wool can also be used to scour away rust.
Chainmail scrubbers are another popular choice for cleaning cast iron without the use of soap. Plus, they can double as a costume for the Renaissance Faire enthusiasts among us!