Reviving Rusty Cast Iron: A Step-By-Step Guide To Restoring Your Pan's Glory

A rusty cast iron pan is no reason to panic. With a few simple steps, you can restore your cookware to its former glory and it will be as good as new. This guide will take you through the process of removing rust, cleaning, and re-seasoning your cast iron pan to ensure it lasts a lifetime.

Soak in vinegar

If your cast iron pan has a lot of rust, you'll need to soak it in vinegar. Start by mixing equal parts water and distilled white vinegar in a container that will fit your pan, such as a bucket or a deep foil pan. Make sure the container is thoroughly cleaned. Then, submerge your pan completely in the mixture, including the handle.

Check the pan every 15 minutes or so. The vinegar solution will dissolve the rust, but it's important not to leave the pan in the solution for too long, as it can start to eat away at the original cast surface of the pan. The maximum amount of time you should leave your cast iron soaking in vinegar is eight hours, but the length of time will depend on how much rust there is to clean. A minimum of one hour is typically needed for an average rusty pan, and you should see the rust starting to fall away from the iron surface after this. Once the rust easily flakes away, remove the pan from the solution.

After soaking, wash your pan with a drop of mild dish soap and warm water, and clean away any lingering rust with a mildly abrasive sponge. It may take some elbow grease, depending on the severity of the cast iron rust. Always use warm water to clean your cast iron after cooking, so it doesn’t warp or crack from a shock of cold, and to 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, since there’s no seasoning to damage.

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 dry it further.

Scrub with salt

If your cast iron pan has a few rusty spots, a salt scrub will do the trick. For this, you'll need about 1/3 cup of kosher salt. Using a scouring pad or kitchen towel, rub the salt into the surface of the pan until the spots of rust have been removed. This method is a great alternative to a vinegar soak, which can be used for more serious cases of rust.

After scrubbing the pan with salt, you'll want to wash the pan with a drop of mild dish soap and warm water. Clean away any lingering rust with a mildly abrasive sponge, like a green scrub pad. Always use warm water to clean your cast iron pan after cooking, so it doesn't warp or crack from a shock of cold. It's okay to use a small amount of soapy water on cast iron, especially since you'll be re-seasoning the pan after cleaning.

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's completely dry.

Wash with soap

Once you have soaked your cast iron pan in vinegar (if necessary) and scrubbed away the rust, it's time to wash it with soap. You can use a small amount of mild dish soap and warm water. Wash your pan with a drop of mild dish soap and warm water, and clean away any lingering rust with a mildly abrasive sponge, such as a green scrub pad. It may take some elbow grease, depending on the severity of the cast iron rust.

Despite the myths, it is okay to use a small amount of soapy water on cast iron at any time, especially at this point, since there is no seasoning to damage. Large amounts of soap can strip the seasoning off your pan, but you can easily re-season your pan as needed.

Always use warm water to clean your cast iron after cooking, so it doesn’t warp or crack from a shock of cold, and it will also speed up the drying process.

Once you have washed your pan with soap, 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 dry it further.

Dry on the stove

After washing your cast iron pan, it is important to dry it promptly and thoroughly. Use a lint-free cloth or paper towel to pat it dry. If you notice any black residue on your towel, don't worry—it's just the seasoning and is perfectly normal.

To ensure your pan is completely dry, place it on the stovetop on low heat for a few minutes. This extra step will ensure that your pan is ready for the next step in the restoration process: reseasoning.

Reseasoning your cast iron pan will 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. This protective layer will also guard against future rust.

To begin reseasoning, preheat your oven to 450–500 °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 aluminum foil or a baking sheet on the bottom rack 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.

Re-season

If your cast iron pan has become rusty, it's important to re-season it to restore the protective layer of fat molecules that bind to the pan, creating a non-stick surface and signature dark matte finish. Here's how to do it:

• Scrub and wash the pan: Use steel wool or a scouring pad to scour the rusty sections of the pan. Then, wash the pan with warm, soapy water to remove any remaining rust and dirt. This step may remove portions of the seasoning, but that's okay as you're preparing to re-season the pan.
• Dry the pan: Completely dry your cast iron pan with a paper towel or lint-free cloth. You can also place it on the stovetop on low heat for a few minutes to ensure it's completely dry.
• Add a thin layer of cooking oil: Using a cloth or lint-free paper towel, add a very thin layer of cooking oil to the entire surface of the pan, including the bottom and handle. Be sure to use just enough oil to create a thin layer that doesn't drip or run when you tilt the pan. Thin layers are important for baking seasoning into the pan.
• Preheat the oven: Preheat your oven to 450-500 degrees Fahrenheit. Place aluminium foil on the bottom rack of the oven to catch any excess oil.
• Place the pan in the oven: Place your cookware upside down on the centre or top rack of the oven. This helps prevent oil from pooling on the cooking surface.
• Bake for 1 hour: Bake the pan for 1 hour at 450-500 degrees Fahrenheit.
• Allow the pan to cool: Turn off the heat and allow the cast iron pan to cool down in the oven. This allows the seasoning to further cure and adhere to the iron.
• Repeat as necessary: If your pan still looks dull after re-seasoning, repeat the process until it achieves a slight sheen.

By following these steps, you can restore your rusty cast iron pan to its former glory and continue using it for decades to come.

Frequently asked questions