Cast Iron Revival: Removing Rust From Your Pan

Cast iron pans are beloved for their durability and longevity, but they're not invincible. If you've left your pan to soak, put it in the dishwasher, or forgotten to dry it off, you may find yourself facing a layer of rust. Luckily, there are several ways to remove rust from a cast iron pan and restore it to its former glory. Some common methods include scrubbing with steel wool or a scouring pad, soaking in vinegar, or using coarse salt to scrub away the rust. Once the rust is removed, it's important to re-season the pan to protect it from future rusting.

Soak in vinegar

So, you've let your cast-iron pan sit in the sink for too long, or maybe you forgot to dry it after washing. Now, it's plagued with rust. Don't worry, it's a common problem, and there's no need to throw your pan away. Cast-iron cookware is meant to last a lifetime, so even if your pan is far gone, it is possible to restore it to its peak form. Here's how to do it:

Firstly, if you’re dealing with minor surface rust, you can probably skip this step and opt for a salt scrub instead. However, for more serious cases, start with a vinegar soak. Mix equal parts water and distilled white vinegar in a container that will fit your rusty cast-iron pan, such as a bucket or a deep foil pan. Make sure the entire pan, including the handle, is submerged in the mixture. Check the pan every 15 minutes or so, and remove it from the solution once the rust easily flakes away. This process can take anywhere from one to eight hours, so frequent check-ins are important to ensure your pan doesn’t soak for longer than necessary. The vinegar solution will dissolve the rust, but once that’s gone, it can penetrate further and start eating away at the original cast surface of the pan, so keep an eye on it.

Next Steps

After soaking, use steel wool or a stiff brush to scrub the skillet again. The vinegar will have broken down the rust, making it easier to remove. If you still see some rust spots, mix baking soda with a small amount of water to create a paste. Apply the paste to the rusted areas and scrub with the steel wool or brush. Then, rinse the skillet thoroughly with water to remove any remaining vinegar or baking soda.

Finally, dry the skillet completely using a kitchen towel or paper towel, and place it on the stovetop over low heat for a few minutes to ensure it's completely dry. Now, your pan is ready to be re-seasoned.

Scrub with salt

If your cast iron pan has only a few rust spots, a salt scrub will do the trick. Start by pouring about 1/3 cup of kosher salt into the pan. Then, grab a scouring pad or kitchen towel and rub the salt into the surface of the pan until the rust spots disappear. Depending on how much rust there is, this may take some elbow grease! But it's worth it to get your pan looking like new again.

If your pan is only lightly rusty, you can skip the vinegar soak beforehand and go straight to the salt scrub. However, if your pan has more serious rust, you may want to start by soaking it in a mixture of equal parts water and distilled white vinegar. Make sure to check the pan every 15 minutes and take it out of the solution once the rust easily flakes away.

After you've finished scrubbing with salt, wash the pan with mild dish soap and warm water to remove any remaining salt and rust residue. Then, dry the pan immediately and thoroughly with a kitchen or paper towel. You can also place the pan on the stovetop over low heat for a few minutes to ensure it's completely dry.

Once your pan is rust-free and dry, it's important to reseason it to restore the protective layer of fat molecules. Simply preheat your oven to 500°F, wipe the pan with a thin layer of neutral cooking oil, and place it upside down in the oven for an hour. Then, turn off the heat and let the pan cool in the oven overnight or remove it and set it aside for at least 45 minutes before using.

Wash with dish soap

If your cast iron pan has rusted, don't panic! It can be easily restored to its former glory.

After removing the majority of the rust, you will need to wash your pan with a drop of mild dish soap and warm water. You can use a mildly abrasive sponge, such as a green scrub pad, or a scrubber made from palm fibres. It may take some elbow grease, depending on the severity of the rust. Always use warm water to clean your cast iron after cooking, so it doesn't warp or crack from the shock of cold water, and it will also speed up the drying process.

Despite the myths, it is okay to use a small amount of soapy water on cast iron at any time, especially at this point, as there's no seasoning to damage. In fact, it is important to use dish soap to ensure that all remaining rust is removed. However, be sure not to use too much soap, as this can strip away the pan's seasoning, making the skillet less rust-resistant.

After washing, dry the pan immediately and thoroughly with a kitchen or paper towel. Set it on the stovetop over low heat for a few minutes to ensure it is completely dry.

Dry with paper towels

Once you've washed your cast iron pan with hot water and dish soap, scrubbed it with coarse salt, and soaked it in vinegar, it's time to dry it. It's important to dry your cast iron pan thoroughly and immediately with paper towels or a clean dish towel. Leaving cast iron to air dry is a common cause of rust, so it's crucial to dry it as quickly as possible. Make sure to get the bottom and handle, too. You can also place the pan on the stovetop over low heat for a few minutes to ensure it's completely dry.

After drying, your pan will be ready for the next step: coating it with a thin layer of cooking oil and placing it in the oven to restore its protective layer of fat molecules, creating a non-stick surface and signature dark matte finish.

To prevent rust in the future, always dry your cast iron pan immediately after washing and store it in a low-humidity spot. If you're stacking multiple pans, line each one with a few layers of paper or kitchen towels, or invest in breathable pan separators to prevent moisture from becoming trapped.

Re-season in the oven

Once your cast-iron pan is free of rust, it's time to re-season it. Here's a detailed, step-by-step guide:

Step 1: Wash and Dry Your Pan

Give your pan a good scrub with warm, soapy water. This step is important, especially if you've been using other methods to remove the rust. You want to ensure that any remaining residue or rust particles are removed before you start the re-seasoning process. After scrubbing, dry the pan thoroughly with a clean cloth or kitchen towel.

Step 2: Apply a Thin Layer of Cooking Oil

Take a cloth or lint-free paper towel and add a very thin, even layer of cooking oil to the entire surface of the pan, including the inside, outside, and handle. Go easy on the oil—you just want a thin layer that is not enough to drip or run when you tilt the pan. This step is crucial for creating a non-stick surface and preventing future rust.

You can use a variety of cooking oils for this purpose, such as vegetable oil, canola oil, or melted shortening. Avoid using too much oil, as it can make your pan sticky.

Step 3: Preheat the Oven and Prepare a Baking Sheet

Preheat your oven to a temperature between 450°F and 500°F. Place a large baking sheet or a piece of aluminium foil on the bottom rack of the oven to catch any excess oil that may drip during the process.

Step 4: Place the Pan Upside Down in the Oven

Place the oiled pan upside down on the centre rack of the preheated oven. This placement prevents oil from pooling inside the pan and helps create an even coating.

Step 5: Bake the Pan

Bake the pan at the preheated temperature for about an hour. It may get a little smoky, so ensure your kitchen is well-ventilated. During this time, the oil will undergo a process called polymerization, where it heats and forms a hard, plastic-like coating that bonds to the metal.

Step 6: Turn Off the Oven and Let the Pan Cool

After an hour, turn off the oven and let the cast-iron pan cool down completely inside. This step allows the seasoning to cure and adhere better to the iron.

Tips for Future Care:

• Oil your iron skillet after each use for long-term care.
• A well-seasoned skillet will have a distinct dark, semi-gloss finish.
• If you rarely use your cast-iron skillet, oiling it two to three times a year should be sufficient.
• Avoid cooking acidic foods, fish, or eggs in cast iron to prevent sticking and rusting.
• Use a nylon scrubber for regular cleaning, and only use more intensive scrubbing if absolutely necessary.
• After cleaning, rub a little oil onto the pan to protect the surface.

Frequently asked questions