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How to Clean and Season a Cast-Iron Pan

Everything you need to know to care for your cast-iron skillet, from everyday upkeep to overhaul duty.
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Published Nov. 29, 2016.

How to Clean and Season a Cast-Iron Pan

What's not to love about cooking in cast iron? We love this pan for its exceptional heat retention, naturally nonstick surface, and unbeatable durability and value. Cast iron is virtually indestructible and is easily restored if mistreated. Plus, a good skillet can be had for well under $50 and should last for generations.

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THE BEST CAST-IRON SKILLETS

In our recent testing of cast-iron skillets, we found two winners: The Smithey Ironware No. 12 Cast Iron Skillet, with a smooth, polished interior and a classic shape, aced all our tests, searing, baking, and browning beautifully and releasing food like a nonstick pan would. But it’s about $200, so we also chose a Best Buy: The Lodge 12 Inch Cast Iron Skillet, which, at about $44, offers equivalent performance at a bargain price.

→ Read our review of traditional and enameled cast-iron skillets

Caring for a cast-iron skillet is like caring for a car: Service it regularly and it will last a long time; use it hard (or neglect it) and it will need more heavy-duty repair work. These care guidelines will bring your skillet back to life, no matter what condition it’s in.

How to Clean a Cast-Iron Pan

This is the best way to care for and maintain a cast-iron pan that's in good shape.

1. CLEAN CAST-IRON SKILLET AFTER EVERY USE

Wipe interior surface of still-warm skillet with paper towels to remove any excess food and oil. Rinse under hot running water, scrubbing with nonmetal brush or nonabrasive scrub pad to remove any traces of food. (Use small amount of soap if you like; rinse well.) Need to remove stubborn stuck-on food and grime? See our more intensive cleaning tips for tackling them.

2. LIGHTLY OIL AFTER EACH CLEANING

Dry skillet thoroughly (do not drip-dry), then heat over medium-low heat until all traces of moisture have evaporated. Add 1/2 teaspoon oil to pan and use paper towels to lightly coat interior surface with oil. Continue to wipe surface with oiled paper towels until it looks dark and smooth and no oil residue remains. Let pan cool completely.

How to Season a Cast-Iron Pan

Found an old skillet that's looking a bit blotchy, or is your pan in need of some extra TLC to get its seasoning back in business? Here are the necessary steps if your cast-iron pan requires some minor service.

STOVETOP REPAIR

Heat skillet over medium-high heat. Using paper towels dipped in 2 tablespoons oil and held with tongs, wipe surface until oil smokes and there is no remaining oil residue. Repeat oil application 3 to 5 times, making sure oil smokes and letting skillet cool slightly after each application.

OVEN REPAIR

Heat oven to 500 degrees. Using paper towels, rub 1 tablespoon (for 12-inch skillet) or 2 teaspoons (for 10-inch skillet) oil over surface. Using clean paper towels, thoroughly wipe out excess oil (surface should look dark and smooth). Place skillet in oven for 1 hour. Using potholders, remove skillet from oven and let cool completely.

How to Remove Rust from a Cast-Iron Pan

Over the lifetime of a cast-iron skillet, you’ll usually just need to maintain or touch up its seasoning. But if the seasoning becomes very dull or damaged or if the pan badly rusts, you’ll need to give it an overhaul.

First, try steel wool and soap. Give it a good thorough scrub to remove crusty residue and traces of rust, and get it back to a level surface. You don't need to remove all the seasoning, just the gunky parts. Rinse and dry thoroughly, and reseason on the stove or oven, as described above. If the pan is really too far gone to clean up with a rigorous scrub, it's time to strip the pan.

STRIPPING A CAST-IRON PAN

To breathe new life into a cast-iron skillet in very bad condition, start by stripping the surface (and then reseasoning it). Once the skillet’s seasoning has been stripped away, follow the oven repair directions (described in previous section), repeating the process six times or until the skillet has a dark, smooth finish.

What is Seasoning?

When fat or cooking oil is heated to its smoke point in cast iron, its fatty acids oxidize and reorganize (or “polymerize”) into a new plastic-like layer of molecules. This layer becomes trapped within the pitted surface of the pan and bonds to the metal itself, creating the slick coating known as seasoning. Repeated exposure to smoking hot oil continues to build on this coating, making it more slippery and durable. That’s why even though most skillets these days come with a factory seasoning, the surface will become even more nonstick with repeated use.

What Oil Should You Use for Seasoning?

The more polyunsaturated the fat, the more readily it will oxidize and polymerize. We have found that flaxseed oil, which oxidizes and polymerizes faster than other vegetable oils, forms a particularly durable seasoning. But cheaper oils such as sunflower and soybean also work fine.

Best: flaxseed oil (9% saturated, 18% monounsaturated, 68% polyunsaturated)

THE ULTIMATE WAY TO SEASON CAST IRON

Although lengthy, this particular method of seasoning with flaxseed oil is a mainly hands-off undertaking. We highly recommend the treatment. In our tests, the flaxseed oil so effectively bonded to the skillets, forming a sheer, stick-resistant veneer, that even a run through our commercial dishwasher with a squirt of degreaser left them totally unscathed.

→ Read our step-by-step guide

Good, lower-cost choices: sunflower oil (10% saturated, 20% monounsaturated, 66% polyunsaturated), soybean oil (16% saturated, 23% monounsaturated, 58% polyunsaturated), corn oil (13% saturated, 28% monounsaturated, 55% polyunsaturated), canola oil (7% saturated, 63% monounsaturated, 28% polyunsaturated)

Worst: bacon fat (39% saturated, 45% monounsaturated, 11% polyunsaturated)

How to Test If Your Cast-Iron Pan is Well Seasoned

A well-seasoned skillet will have a dark, semiglossy finish and won’t be sticky or greasy to the touch. It won’t have any rust or any dull or dry patches.

DOES IT PASS THE FRIED EGG TEST?

An easy way to test a skillet’s seasoning is to fry an egg (heat 1 tablespoon vegetable oil in skillet over medium heat for 3 minutes, then add egg). If your pan is well seasoned, you should not experience any major sticking.

→ Try our recipe for Perfect Fried Eggs

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