The Art Of Re-Seasoning Cast Iron: A Step-By-Step Guide

Cast iron pans are a heavy-duty kitchen essential, but they need to be well-maintained to perform at their best. One of the most important steps in caring for your cast iron pan is seasoning—a process that creates a hard, protective coating to prevent rusting and food from sticking. Seasoning involves filling in the pores of the skillet with cooking oil or fat, which changes the colour to dark grey/black and creates a natural non-stick surface. This guide will take you through the steps to reseason your cast iron pan, so grab your oil and oven mitts and let's get started!

Cleaning the pan

Cleaning a cast-iron pan is a simple process, but there are a few things to keep in mind to ensure you don't damage the pan's seasoning or cause rust. Here's a step-by-step guide to cleaning your cast-iron pan:

Step 1: Clean the pan while it's still hot. It's best to clean your cast-iron pan immediately after use. Waiting until the pan has cooled will make it harder to remove stuck-on food.

Step 2: Wash the pan with hot water. Fill your cast-iron pan with hot water and scrub it firmly with a sponge, brush, or scrubber. Avoid using soap, as it can strip the seasoning from your pan. If there are stuck-on bits of food, you can use a paste of coarse kosher salt and water to scrub them off. Alternatively, you can try boiling a little water in the pan to loosen the residue.

Step 3: Dry the pan thoroughly. After washing, dry your cast-iron pan thoroughly with a clean cloth or paper towel. Make sure to remove all moisture to prevent rusting. You can also place the pan on the stove and heat it gently to ensure all the water evaporates.

Step 4: Apply a light coat of oil. Once the pan is completely dry, use a cloth or paper towel to apply a light coat of oil to the inside of the skillet. This will help maintain the pan's seasoning and prevent rusting. Oils such as vegetable oil, canola oil, or shortening are recommended.

Step 5: Store the pan in a dry place. After oiling, store your cast-iron pan in a dry place until your next use. You can hang it or stack it with paper towels in between pans to protect the finish.

It's important to note that you should never soak your cast-iron pan in water or put it in the dishwasher, as this can lead to rusting. Additionally, avoid using steel wool or other abrasive materials when cleaning, as they can damage the pan's seasoning. If your pan does develop rust, you can remove it by scrubbing with steel wool and warm water or using a combination of half a raw potato and a sprinkle of baking soda. Remember to re-season your pan after removing rust.

Drying the pan

Drying your cast iron pan is essential to its maintenance. Cast iron is highly susceptible to rusting when exposed to oxygen and water. While seasoning your pan can help protect it from rust, it is not enough on its own. Your pan should never be left to air-dry, soak, or go in the dishwasher.

There are several ways to dry your cast iron pan:

Lint-free Towel

This is the most common and quickest method. You can use a lint-free cloth, an old t-shirt, or a paper towel. However, be careful not to scrub the pan dry with a paper towel, as this can transfer lint. Make sure to get the pan completely dry with no moisture left behind.

Stovetop

This method involves placing the pan over a medium flame for about 5 minutes to ensure it is thoroughly dry. It is recommended to first dry the pan with a towel and then place it on the stovetop to ensure any remaining moisture is removed. This method is also believed to preserve and maintain the seasoning on the skillet.

Oven

This is the least common method for drying a cast iron pan, as it is more time-consuming. However, if you plan to season the pan in the oven, you can put it in the oven while it is preheating to kill two birds with one stone.

Oiling the pan

When it comes to oiling the pan, the first step is to ensure that the pan is completely dry. Any moisture that remains in the pan can cause the oil to become sticky or grimy, so it is important to wipe the pan down with a paper towel or dish linen, and then place it on the stove over a medium heat until all the moisture has evaporated. You will know the pan is completely dry when you can smell the heat coming off it.

Once the pan is dry, it is time to add the oil. Use a paper towel to rub the oil in evenly across the entire pan, inside and out—including the handle. You can use a variety of cooking oils, such as canola, vegetable, grapeseed, sunflower, safflower, or flaxseed oil. Avoid using butter or unrefined coconut oil, as the dairy solids and pulp will burn and scorch. You only need a very thin layer of oil on the pan; if the pan looks greasy or slick, you have used too much. Keep buffing the oil into the pan until it no longer looks greasy.

After the oil has been applied, the pan is ready to be placed in the oven. Place the pan upside down on a middle oven rack to prevent the oil from pooling, and put a sheet of aluminium foil on the lower shelf to catch any drips. Preheat the oven to at least 450°F, or 230°C. The goal is to heat the oil past its smoking point, which triggers a chemical reaction called polymerization that bonds the oil to the pan.

Leave the pan in the oven for 30 minutes to an hour. You will see some smoke coming from the pan as the oil begins to polymerize. Once the smoke is gone, you know the polymerization process is complete.

You can repeat the oiling and heating process three to four times to set down a good initial layer of seasoning. After the final round of heating, turn off the oven but leave the pan inside as it cools. This helps to solidify the layers of seasoning.

Heating the pan

Once the oil has been applied, place the pan upside down in the oven. This will prevent the oil from pooling inside the pan. Place a sheet of aluminium foil on the lower shelf to catch any drips.

Preheat your oven to between 350˚F and 500˚F. Lodge recommends a temperature of 450-500˚F, while other sources suggest 350˚F or 450˚F. The higher temperature of 450-500˚F is recommended if you are using canola oil, which has a smoke point of 400˚F.

Place the pan in the oven and bake for 30 minutes to 1 hour. You will know the process is working when you see smoke radiating from the pan as the oil begins to polymerize. After the smoke has cleared, the polymerization process is complete.

Once the time is up, turn off the oven and leave the pan inside to cool completely. This helps to solidify the layers of seasoning.

Cooling the pan

Allowing your cast iron pan to cool down slowly is essential to prevent thermal shock, which can ruin your pan. Cast iron is designed to maintain heat, so it will take a while to cool down. However, there are a few things you can do to speed up the process slightly.

Firstly, ensure you have removed the pan from the heat source. You can then try swinging the pan (if it is empty). Adding a small amount of water to the pan can also help to cool it down, but be careful not to add too much cold water, as this can also cause thermal shock and crack the pan. If you are cooking pasta, you can add some of the pasta water to the pan to help cool it down without causing a rapid temperature change.

If you are cooking something that requires a lower temperature, such as eggs, it is best to start by cooking the ingredients that need a high temperature first and setting them aside. You can then use the same pan for the low-temperature ingredients without having to worry about cooling it down.

Another option is to use a heat sink, such as a big block of metal, to pull heat away from the pan. However, this will still take some time, and you will need to be careful not to place a hot pan directly on a surface that could be damaged by the heat, such as a wooden table or a refrigerator.

In general, it is best to plan your cooking in advance and allow your cast iron pan to cool down slowly to avoid damaging it. Cast iron pans are designed to maintain heat, so they are not the best choice if you need to cook multiple dishes at varying temperatures quickly.

Frequently asked questions