Liberating Your Cast Iron: The Ultimate Guide To Derusting

Removing rust from a cast iron pan is a simple process that can be done at home. While it may seem tempting to throw away a rusty cast iron pan, it is important to remember that cast iron cookware is meant to last a lifetime. By following a few easy steps, you can restore your pan to its former glory and continue using it for decades to come. The first step is to remove the rust, either by scrubbing with steel wool or by soaking the pan in vinegar. After removing the rust, the pan should be washed, dried, and then coated with a thin layer of cooking oil. Finally, the pan is placed in the oven for an hour and allowed to cool before use.

How to Derust a Cast Iron Pan

Soak in vinegar

If your cast iron pan has a lot of rust and is considered unusable, you can try a vinegar soak. This method may be shocking to some cast-iron users as submerging the pan in liquid is usually a major no-no. However, it is a good way to remove rust and you can always re-season the skillet before using it to cook again.

To start, mix equal parts water and distilled white vinegar in a container that will fit your rusty cast-iron skillet, such as a bucket or a deep foil pan. Make sure the entire pan is submerged in the mixture, including the handle. Check the pan every 15 minutes or so and remove it from the solution once the rust easily flakes away. This process can take as little as an hour or up to eight hours, so it's important to check frequently to ensure your skillet 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 don't leave it too long.

Once the rust has been removed, rinse the pan thoroughly with water. Dry the skillet completely, either with a towel or by placing it on the stovetop over low heat for a few minutes. Then, re-season the cast iron by preheating the oven to around 500°F. Wipe a thin layer of neutral cooking oil with a high smoke point, like vegetable oil, all over the entire pan—inside and out. Then, buff any excess oil and set the pan upside-down in the oven, with aluminium foil or a baking sheet on the rack below to catch any drips. Turn off the heat after an hour and let the pan cool in the oven overnight, or remove the pan and set it aside for at least 45 minutes before using.

Scrub with steel wool

Removing rust from a cast-iron pan can be done in several ways, but one of the most popular methods is to scrub the affected areas with steel wool. This process can be time-consuming, so it is recommended to put on some music to make the task more enjoyable. The type of steel wool used is important; fine steel wool is best for scouring the skillet until the rusty areas return to raw cast iron. It is normal to be concerned about scratching the pan, but cast iron is durable and will not be scratched easily. After the rust has been removed, the pan will need to be washed, dried, and reseasoned.

When scrubbing a cast-iron pan with steel wool, it is important to be thorough and cover all the rusty areas. This may include not just the inside of the pan but also the bottom, handle, and outside. A Lodge Rust Eraser can also be used for this step. Once the rust has been removed, the pan should be washed with warm, soapy water. This step may remove portions of the seasoning, but that is okay, as the pan will be reseasoned.

After scrubbing and washing the pan, it is important to dry it thoroughly. This can be done with a paper towel or lint-free cloth, and the pan can be placed on the stovetop on low heat for a few minutes to ensure it is completely dry. Proper drying is crucial to prevent the pan from warping or cracking from exposure to moisture. Once the pan is dry, a very thin layer of cooking oil should be added to the entire surface. This helps to restore the protective layer that prevents rust and creates a non-stick surface.

To reseason the cast iron pan, preheat the oven to between 450 and 500 degrees Fahrenheit. Place a sheet of aluminum foil on the bottom rack of the oven to catch any excess oil. Then, place the pan upside down on the centre rack to prevent oil from pooling on the cooking surface. Bake for one hour, then turn off the heat and allow the pan to cool in the oven. This curing process helps the seasoning adhere to the iron, creating a protective layer that will guard against future rust.

Wash with soapy water

Once you've removed the rust from your cast iron pan, it's time to give it a good wash with soapy water. Contrary to what some people believe, washing your cast iron with soap is perfectly safe and effective. In fact, it's a much quicker and easier method than the traditional way of cleaning cast iron.

To wash your cast iron with soapy water, start by wetting your pan with warm water. Then, add a small amount of mild dish soap and scrub the pan with a sponge or bristle brush. You can also use the abrasive side of the sponge if needed. If you're dealing with particularly stubborn stuck-on food, you can simmer a little water in the pan for 3-5 minutes before scrubbing. Just be sure to let the pan cool down before scrubbing.

After scrubbing your pan with soapy water, make sure to rinse it thoroughly to remove any soap residue. Then, dry the pan promptly and thoroughly with a lint-free cloth or paper towel. You can also place the pan on the stovetop on low heat for a few minutes to ensure it's completely dry.

While washing your cast iron with soapy water is a convenient option, it's important to note that using large amounts of soap can strip the seasoning from your pan. So, be sure to use only a small amount of soap, and if you're concerned about removing the seasoning, you can always re-season your pan after washing.

Dry on the stove

Once you've scrubbed and washed your pan, dried it with a towel, and applied a thin layer of oil, you'll want to dry your cast iron pan on the stove. Place the pan on the stovetop on low heat for a few minutes to make sure it's completely dry. This step is important because any lingering dampness can encourage rust to return.

After drying your pan on the stove, you'll need to season your pan to restore the protective layer of fat molecules that bind to the pan, creating the cast iron's non-stick surface and signature dark matte finish.

To season the pan, preheat your oven to 450–500 degrees F. Wipe a thin layer of neutral cooking oil with a high smoke point, like vegetable oil, all over the entire pan—inside and out. Then, buff any excess oil and set the pan upside down in the oven, with a sheet of aluminum foil or a foil-lined baking sheet on the bottom rack to catch any oil drips. Heat the cast iron for one hour at 350–500 degrees F.

Turn off the heat and allow the cast iron skillet to cool in the oven. This allows the seasoning to further cure and adhere to the iron.

Re-season with oil

Re-seasoning a cast iron pan with oil is a simple process, but it does require a few steps to ensure your cookware is protected and ready for cooking.

Firstly, scrub and wash your pan. Use steel wool to scour the rusty sections, and then wash the pan with warm, soapy water. This step may remove some of the seasoning, but that's okay as you are preparing to re-season the pan.

Next, dry the pan thoroughly. Place the pan on the stovetop on low heat for a few minutes to ensure it is completely dry.

Now, you can add a thin layer of cooking oil to the entire surface of the pan, including the handle. Go easy on the oil—a thin layer is important for baking seasoning into the pan. You want to avoid a sticky surface, so use a cloth or lint-free paper towel to apply the oil.

Preheat your oven to between 350-500 degrees Fahrenheit. Place a sheet of aluminum foil on the bottom rack to catch any excess oil drips. Place the pan upside down on the centre or top rack. This will help prevent oil from pooling.

Bake the pan for one hour. Then, turn off the heat and allow the pan to cool in the oven. This allows the seasoning to cure and adhere to the iron.

Your pan is now ready for cooking. However, if you want to build up a strong layer of seasoning, you can repeat the oiling-and-heating process three to four times.

Frequently asked questions