How To Clean Cast Iron (And How To Season It!)

Cast iron cookware has always held a special place in my heart because it’s economical, durable, versatile, retains heat well, and cooks food evenly. And when it is properly cleaned and cared for, cast iron can last for generations—quite literally!

I use my cast iron skillets to make all sorts of delicious creations, like pan-seared steaks, berry cobbler, and chocolate fudge skillet cake. I’ve even turned a cast iron skillet upside down and used it in my oven as a makeshift “pizza stone!”

And although I’ve mentioned cooking in cast iron skillets several times in blog posts over the years, I realized I had neglected to share how to clean cast iron or care for it—until now, that is! So today I’m going to do just that by sharing my super simple guide to cleaning and caring for cast iron cookware.

How To Clean Cast Iron

When you clean a cast iron skillet, the more gently you can do it, the better off you’ll be. If your cast iron skillet isn’t all that dirty after cooking in it, you may find that you can clean it up simply by wiping it out with a paper towel or a dish cloth!

If you need a little more cleaning power, pour a handful of coarse kosher salt into your still-warm pan, then add enough vegetable oil to the kosher salt to form a gritty paste. Use a clean, dry dish rag to scrub the kosher salt and oil paste around the inside of the pan.

The salt will provide the extra scouring power you need to remove those stuck-on food bits, while the oil soaks up the grime and helps to build up the seasoning on your pan. When you’re done scrubbing, dump the salt mixture out and wipe up any residual salt and oil with a paper towel or another clean rag.

4 Rules To Remember When Cleaning Cast Iron

As I’m sure you can gather from the instructions above, cleaning cast iron isn’t exactly complicated. But there are a few rules you should follow in order to avoid damaging your cast iron in your quest to keep it clean:

Clean it promptly after each use.
Don’t soak it.
Use the right tools.
Dry it thoroughly after cleaning.

Rule #1: Clean It Promptly

Cast iron is easiest to clean while it’s still hot or warm. And lest you worry that means you have to clean the pan before you can sit down and enjoy your meal, keep in mind that cast iron holds onto heat a lot longer than other materials, so it will stay warm for a lot longer than you might think!

Rule #2: Don’t Soak It

Raw or exposed cast iron can easily rust if it’s exposed to too much moisture. And although a pan that’s properly cared for won’t usually rust because of its protective seasoning, even that will start to break down if the pan is submerged in hot water for too long.

For those reasons, you should not clean a cast iron skillet by soaking it. Even if there are stubborn stuck-on food bits, soaking it in hot water will do more harm than good! (And even if it seems obvious, it bears repeating—avoid using the dishwasher at all costs!)

Rule #3: Use The Right Tools

When tackling more serious messes in a cast iron pan, using the right tools will make all the difference. If the mess is more than a paper towel or a salt-and-oil scrub can handle, use the scrubby side of a sponge or a heat-safe brush designed specifically for cast iron to remove stuck-on food bits. (This brush even has a handy scraping edge for tackling particularly stubborn gunk.)

If those don’t get the job done, you can use hot water, a small amount of mild dish soap, or even a piece of steel wool to clean your cast iron pan. Keep in mind that both dish soap and steel wool can wear down the seasoning on your pan over time. So just don’t use soap or steel wool any more frequently than you have to.

(If you accidentally scoured off more of the seasoning on your pan than you intended to, never fear! You can easily restore it by following the instructions under “How To Season Cast Iron” below.)

Rule #4: Dry It Thoroughly

When you’re finished cleaning your cast iron pan, it’s important to dry it thoroughly right away. Use a lint-free cloth or paper towel to dry the pan inside and out to prevent any rust from forming due to lingering moisture.

What Is Seasoning, And Why Is It Important?

When it comes to caring for cast iron, keeping it clean is only part of the equation. Seasoning cast iron (or maintaining a well seasoned skillet) is equally important, but what exactly is “seasoning” anyway?

Well, when fats and oils are heated to their smoke point in a cast iron vessel, the fatty acids oxidize and reorganize in a process called polymerization. This new, plastic-like polymerized layer adheres to the pitted surface of the pan, creating the dark-colored, non-stick coating known as seasoning.

And the more you use the pan to heat fats or oils to high temperatures, the more durable and non-stick the seasoning on your pan will become. That’s why it’s important to build that layer up so that it becomes more well seasoned over time, even though many modern cast iron skillets come “pre-seasoned.”

How To Season Cast Iron

To season a cast iron skillet, start by applying a light coat of oil or fat to the entire pan, including the inside, outside, bottom, and even the handle. Vegetable oil, sunflower oil, soybean oil, corn oil, and canola oil all work well here, because they are high in polyunsaturated fats that polymerize readily.

Preheat your oven to 350°F, then “bake” your oiled pan or skillet for one hour. To help keep your oven clean, you may want to place a baking sheet lined with tin foil on the rack beneath the pan to catch any oil drips. (But as long as you haven’t gone overboard with the oil, it shouldn’t drip much at all as it bakes!)

After an hour, turn off the oven and let the pan cool inside. Then when it’s cool enough to handle, remove the pan and remove any excess oil with a lint-free cloth or paper towel. Read more here!

How To Remove Rust From Cast Iron

Whether you’ve inherited an old, rusty cast iron skillet, or you accidentally broke Rule #2 of cleaning cast iron, the good news is that it isn’t too difficult to restore rusty cast iron. And all you need is some fine steel wool, a bit of soap, and a sponge to do it!

Start by using steel wool to scrub the rusty areas of the pan. Add a bit of water and scour until the raw cast iron is exposed. (Look at the color—the raw cast iron will quite a bit lighter than the dark seasoned layer.)
Once the rust is gone, wash the pan with soap and water, then dry the pan right away. Take your time and make sure the pan is completely dry, otherwise the rust might return and you’ll have to start all over!
Once your pan is dry, you’ll need to season it again following the instructions provided in previous section. Once you’ve done that, your previously rusty cast iron will be fully restored and ready to use again!

With the help of these tips and techniques, your well-seasoned cast iron will serve you well for decades to come. Oh, and one last thing before you go… give this cast iron skillet cookie recipe a try, and you can thank me later! ;-)