How to Clean and Season Cast Iron Cookware

Monday, April 8, 2019 Food

Should you use dish soap or no? What about rust? What does it mean to season a skillet, anyway? Follow a few simple easy steps and your cast iron will last for years and years.

Relax. Cast iron care is simple. Here are the two biggest things to remember.

           Dry it before you put it away.

           Don’t put it in the dishwasher.

Easy, right? If  you want to learn about seasoning cast iron, or why cooking tomatoes in a cast iron skillet would even be problematic, keep reading.


Seasoning is what makes cast iron black. The blacker a skillet, the better it is seasoned.

“Seasoning” is the  finish, and also to the process of applying that finish. Generally speaking, Oil + Metal + Heat = Seasoning.

When thinly spread over the cast iron and heated for a long period of time, the fatty acids in oil change chemically, oxidizing and creating a slick layer over the surface of the pan. To the naked eye cast iron looks smooth, but it’s got teeny-tiny nooks and crannies where the oil gets trapped and then bonds with the iron.

So, when you season cast iron, you’re making a do-it-yourself nonstick coating. Cool, huh?

OVER TIME SEASONING GETS BETTER 

The more you cook with cast iron, the better that coating gets.

For best results, get in the habit of seasoning your skillet after most uses. Routine seasoning isn’t hard, and it doesn’t take a lot of time.

Most new skillets these days come pre-seasoned and ready to use. 

HOW TO CLEAN CAST IRON

About that soap: I occasionally wash my cast iron cookware with dish soap on purpose. It’s fine. It will not ruin your skillet. When your skillet is especially greasy, a little dish soap cuts right through it.

But often it’s not necessary to wash cast iron with soap. If you’ve been griddling pancakes, a simple wipe with a paper towel might be all you need. For gunky or saucy foods, keep reading.

SCRUB AWAY YOUR WORRIES

For gunky residue, a wet plastic scrubby or brush gets the job done most of the time. Avoid metal bristles or pads, which can remove the skillet’s seasoning.

Once your skillet has cooled off some, fill it with water, scrub-a-dub-dub, rinse, and presto! It’s clean.

I save the plastic netting from bags of onions or fruit for single-use scrubbies—they work great, for getting crud like melted cheese or cooked egg residue.

Old-time cleaning methods include scouring the skillet with salt or cornmeal. Both of these abrasives are likewise safe and cheap.

HOW DO YOU DRY YOUR SKILLET?

Don’t store your cast iron while it’s still wet because Iron & Water = Rust.How do you dry a skillet? Sounds obvious, but with a towel (cloth or paper). You can let it air-dry, but that could lead to small spots of rust developing if the air circulation is poor.

Some people like to dry their skillets on the stove over low heat for half a minute or so. This works, but if you wander away and forget the skillet is on the stove, you can return to a smoking, red-hot skillet. Not like I’ve ever, ever done anything like that.  Ok maybe once.

WHY CAN’T YOU PUT CAST IRON IN THE DISHWASHER?

I’d always heard dishwashers can strip away the seasoning and make cast iron rust. But I’d never tried it myself,

How to Clean Cast Iron - woman pouring oil into a cast iron skillet on stove

HOW TO SEASON CAST IRON

I’d be lying if I said I seasoned my cast iron every time I used it. Routine seasoning after most uses is probably good enough.

Here’s how to do it: once your skillet is clean, set it on the stove over high heat until it’s dry. Add a small amount of oil—less than a teaspoon—and smear it around well with a paper towel or clean, lint-free rag. Take it off the burner. If it looks especially greasy still, wipe it out again. That’s it!

The seasoning on your skillet isn’t permanent. But after simmering liquids in your skillet, the seasoning will be duller and more vulnerable to rust. Dry-searing in your skillet—as well as unintentionally burning food—can also wear down the seasoning.

When your skillet isn’t looking like its normal self, give just it some love and massage with oil as described above. 

How to Season a Cast Iron Pan - two bottls of vegetable oil

WHAT OIL TO USE FOR SEASONING

Lard was once the choice, but do you have lard around? Probably not. Also, animal fats (like lard or bacon grease) can go rancid. As can olive oil. This said, if you use your skillet every single day, then it’s fine to use these fats for seasoning.

But in general, you want to use an oil with a high smoke point when you season cast iron, particularly if the cast iron was in bad shape. So-called neutral oils like soybean oil, vegetable oil, and canola oil work fine.

For routine seasoning, it’s better to season with an oil that’s not the top choice than it is to neglect to care for your skillet.

How to Clean a Cast Iron Skillet - cast iron skillet upside down in ovenHOW TO RESCUE A RUINED SKILLET

So you found an old skillet at a flea market. Or you put one in the dishwasher. . In any case, now the skillet looks like something You found laying in the ocean.  This should help fix your problem.

 

 

 

 

  • Step 1: Preheat the oven to 350°F.
  • Step 2: Scrub the skillet’s rusty spots with dry steel wool or a metal scrubby. You’ll wind up spreading the loosened rust particles around, and it might not look like you’re making headway. If you wipe away the rusty dust with a paper towel and you’ll see that you are.
  • Step 3: Wash the skillet in warm water, scrubbing it with a stiff brush or scouring pad. You can use a little dish soap, if you like, but it’s not necessary.
  • Step 4: Dry the skillet. If you see rough, rusty spots repeat steps 2 and 3.
  • Step 5: Give your skillet a massage all over with neutral cooking oil such as canola or vegetable oil. Use a lint-free rag or paper towel. Don’t be skimpy, but don’t slather it, either—that can give your seasoning a sticky residue.
  • Step 6: Put the skillet face-down on a rack in the middle of the oven (face-up might cause oil to pool, leaving a sticky residue). Lay a sheet of foil underneath to catch any drips. Bake the skillet for 1 hour. Turn off the oven, and let it cool with the skillet in it (put a Post-It on there so you don’t forget).
  • Step 7: Once the cast iron has cooled, examine it. Repeat steps 5 to 6, if needed. If the situation still looks grim, it’s time for drastic measures.

COOKING ACIDIC FOODS IN CAST IRON

Acid—things like vinegar and tomato sauce—will react with the iron in the metal as they heat. This can cause a metallic taste.

The rule of thumb is moderation: shorter cook times and mild acids. Tomato sauce simmered for half an hour or less should be fine. Also, sauces are less likely to pick up metallic tastes from well-seasoned pans.

Storing acidic foods in cast iron can also lead to a metallic taste. You can avoid this by transferring the food to another container once it’s cool.

How to Clean a Cast Iron Skillet - close up of cast iron pans stacke don top of each other.