Cleaning Cast Iron: Kenji's Comprehensive Guide

Kenji Lopez-Alt, the former culinary director for Serious Eats, has written extensively about cast iron pans, including how to clean and care for them. In his articles, Lopez-Alt debunks common myths about cast iron, provides tips for buying and seasoning vintage cast iron, and offers a comprehensive guide to cleaning and maintaining cast iron cookware. Lopez-Alt's advice covers everything from everyday cleaning and removing rust to completely stripping and re-seasoning a cast-iron pan. By following his recommendations, you can ensure that your cast iron cookware will last for generations.

How to remove stuck-on food from a cast iron pan

Using the Boiling Water Method

If food is stuck to the bottom of your cast-iron pan, don't panic! Simply follow these steps:

• Add 1 to 2 cups of water to the pan.
• Place the pan on a burner and turn the heat up to high.
• Bring the water to a boil and let it simmer for a few minutes.
• Turn off the heat and use a wooden spatula to gently scrape up any remaining food bits.
• Wash the pan with mild dish soap, hot water, and a non-abrasive sponge or scrub brush.
• Dry the pan thoroughly with a dish towel or paper towel.
• Apply a thin layer of neutral oil, such as canola or vegetable oil, to the pan. Use a paper towel or clean rag to rub the oil all over the pan's surface, including the handle.

Using Kosher Salt

If you're looking for an alternative method to remove stuck-on food, try using kosher salt:

• While the pan is still warm, add 1/4 cup of kosher salt and a few drops of warm water.
• Use a non-abrasive sponge or scrub brush to gently scrub the pan and remove the stuck-on food. The salt will dissolve and won't damage the seasoning.
• Wash, dry, and oil the pan as usual.

Preventing Stuck-On Food

To prevent food from sticking to your cast iron pan, it's important to build up a good layer of seasoning. Here are some tips:

• Use the pan frequently, especially for oil-based tasks such as frying or searing.
• Clean the pan immediately after use. Removing food debris is easier when the pan is still hot.
• Re-season the pan regularly by rubbing it with oil and heating it in the oven.
• Avoid using excessive amounts of soap or cooking acidic foods until a good layer of seasoning has been established.

How to dry and store a cast iron pan

Drying and storing your cast iron pan is a crucial step in its maintenance. Here's a detailed guide on how to do it properly:

Drying Your Cast Iron Pan:

• After washing your cast iron pan, it's important to dry it promptly and thoroughly. Use a lint-free cloth or paper towel to absorb any remaining water. Don't leave your cast iron pan to air-dry, as this can lead to rust formation.
• If you notice any black residue on your towel, don't be alarmed; it's just the seasoning coming off, which is perfectly normal.

Storing Your Cast Iron Pan:

• Before storing your cast iron pan, it's essential to ensure that it is completely dry. Place it on the stovetop over low heat or in an oven at a low temperature (200-300°F) to ensure all moisture is evaporated.
• Once the pan is dry, heat a small amount of cooking oil or use a seasoning spray on the surface. Use a paper towel to wipe the surface until no oil residue remains. This step helps create a protective barrier against moisture and air.
• Allow the pan to cool down to room temperature before storing it away.
• Store your cast iron pan in a dry and well-ventilated area. Avoid stacking other items on top of it, as this can damage the seasoning.
• If you plan to store your cast iron pan for an extended period without use, consider giving it an extra coat of oil to protect it from rust.

By following these steps, you'll be able to maintain your cast iron pan in great condition, ensuring it lasts for generations.

How to season a cast iron pan

Initial Seasoning

Scrub your new pan with half a cup of kosher salt and a paper towel to scour out any dust and impurities. Wash the pan with hot, soapy water and dry it carefully. Next, rub down every surface with a paper towel soaked in a highly unsaturated fat like corn, vegetable, or canola oil. Place the pan in the oven at 450°F for 30 minutes until its surface is distinctly blacker. Repeat the oiling and heating steps three to four times until your pan is nearly pitch black.

Maintenance

The best way to maintain the seasoning on cast iron is to use the pan often, particularly for oil-based tasks such as frying or searing. Clean it immediately after use; removing food debris is much easier from a hot pan. In most cases, avoid tough abrasives and use the scrubby side of a soft sponge. Dry thoroughly, reheat, and oil before storing.

How to remove rust from a cast iron pan

Cast iron pans are a versatile workhorse in the kitchen, but they do require some care to keep them in good condition. One of the most common issues is rusting, which can occur if the pan is left to air dry, is soaked in water, or is not seasoned properly. Here is a step-by-step guide on how to remove rust from your cast iron pan:

• Scour the pan with warm, soapy water and steel wool: Start by giving the pan a good scrub. Use a small amount of mild dish soap and warm water, and scrub the pan with steel wool. This will help to remove any stuck-on food or grease.
• Rinse and dry the pan thoroughly: Once you have scoured the pan, rinse it with clean water to remove any soap residue. Then, use a lint-free cloth or paper towel to dry the pan completely. Make sure there is no moisture left on the pan, as this can lead to further rusting.
• Apply a thin layer of cooking oil: After the pan is dry, apply a thin, even layer of cooking oil to the entire surface of the pan, inside and out. You can use vegetable oil, canola oil, or any other neutral oil. Avoid using too much oil, as this can make the pan sticky.
• Place the pan upside down in the oven: Preheat your oven to 450-500 degrees Fahrenheit. Place the oiled pan upside down on the top rack of the oven. Place a baking sheet or aluminum foil on the bottom rack to catch any oil drips.
• Bake the pan for one hour: Let the pan bake for about an hour. This will help to remove any remaining rust and restore the seasoning. After baking, turn off the oven and allow the pan to cool completely inside.
• Repeat as necessary: If there are still signs of rust, repeat the above steps until the pan is completely rust-free and has a dark, smooth patina.

It's important to note that preventing rust is always better than having to remove it. To avoid rusting, always dry your cast iron pan thoroughly after washing and apply a light coat of oil before storing. With proper care, your cast iron pan can last for generations.

How to strip a cast iron pan

Stripping a cast iron pan is necessary when you want to remove old seasoning and rust, and make the pan as good as new. Here is a detailed guide on how to do it:

Inspect the Pan: Before starting the stripping process, it is important to inspect the pan for any cracks. A solid, crack-free cast-iron pan will have a bell-like resonance when you rap the bottom of it with your knuckles. If the sound is dull and clipped, it indicates a likely crack, and such pans should be avoided. Also, look for any pitting or flaws on the cooking surface, as excessive pitting can make it difficult to get an even layer of seasoning.

Don't Use Naval Jelly: Some websites recommend using Naval Jelly, a form of phosphoric acid, to strip the pan. However, this method can be ineffective for larger cookware, as the jelly dries on and becomes difficult to remove.

Use Lye or Oven Cleaner: The seasoning on cast iron is a polymerized oil, which can be broken down using lye (sodium hydroxide). You can use a product like Easy-Off, an oven cleaner that sprays a lye-based foam. Spray the foam all over the pan, seal it in a heavy-duty garbage bag, and let it sit for 24 hours. Then, scrub the pan with a heavy-duty scrubber to remove the seasoning. For larger pans or faster results, you can fill a bucket with a lye solution (one-pound bottle of lye to five gallons of water) and submerge the pan in it for 24 hours before scrubbing. Always exercise caution when handling lye, as it can cause chemical burns.

Remove Rust with Vinegar: Once you've stripped the old seasoning, the next step is to remove any rust. Soak the pan in distilled white vinegar for 6 to 12 hours, then scrub it. Do not let the pan soak in vinegar for more than 24 hours, as it can erode and pit the cast iron.

Prevent Rust with Mineral Oil: Cast iron will start to rust almost immediately once it's been stripped. To prevent this, rub the pan with mineral oil until the shine is gone. Then, wash it with warm soapy water before seasoning the pan.

Season the Pan: After stripping and cleaning the pan, it is essential to season the pan to prevent rust and create a non-stick surface. You can season the pan by rubbing it with a neutral kitchen oil like corn, vegetable, or canola oil, and then heating it in the oven.

Frequently asked questions