Looking after a cast iron skillet is like having a car.
Service it regularly, and it’ll last and last. Neglect it, and you’ll be spending a long time doing heavy-duty repairs.
But despite the high maintenance, cast iron skillets remain one of the most popular choices for cooks, just like you. In fact, according to Statista, U.S. retail sales for cast iron cookware passed $176 million in 2018 alone.
And every year, this figure keeps on rising. So, you’re in good company!
In this guide on how to care for a cast iron skillet, we’ll be discussing:
- How to season
- Why seasoning is important
- What oil is best for seasoning?
- How to clean your cast iron skillet
- How to store them and prevent damage
- Can you use acidic ingredients in cast iron?
- How to remove rust
So there’s a quick glimpse. Now, let’s move on to the good stuff.
How To Season A Cast Iron Skillet
Seasoning is a reasonably straightforward process. It involves baking several layers of oil through a process known as polymerization.
You might need to re-season your cast iron skillet if your food starts to stick to the surface or you notice a rusty, dull appearance. We would suggest seasoning your skillet after using it for maximum results.
Here are some simple instructions on how to season a cast iron skillet.
What you’ll need
- Dish soap
- Paper towels
- Aluminum foil
- Get Ready: Gather everything we’ve mentioned above, and then preheat your oven to 350°F.
- Wash: Wash your skillet with warm, soapy water using either a sponge or stiff brush. In most scenarios, soap shouldn’t be used to wash cast iron. But, a little bit is completely fine.
- Rinse and Dry: Rise your skillet thoroughly to remove excess soap and dry with a clean paper towel.
- Add Oil: Pour 1 tablespoon (for 12″ skillet) or 2 tablespoons (for 10″ skillet) of your preferred cooking oil into the cast iron skillet. We recommend using flaxseed oil due to the high amount of polyunsaturated fat. Other methods suggest using vegetable oil.
- Wipe: Using kitchen tongs and a clean paper towel, rub the oil around the entire surface of the skillet. Be sure to get into the edges too!
- Turn the skillet over: Don’t forget to wipe the oil around the bottom and outside of the skillet. You want the whole skillet to be covered in a thin layer of oil.
- Remove excess oil: With a dry paper towel, remove any clumps of oil that might have gathered together. The layer of oil must be even across the entire piece.
- Bake: Heat your oven to 500°F, then place your skillet upside down on the center rack. Place a sheet of aluminum foil underneath the center rack to catch any oil drips. Bake your skillet for one hour.
- Cool: After an hour, turn off the heat and allow your skillet to cool completely. Once it’s cooled down, get cooking!
Remember: A well-seasoned skillet should have a dark, smooth, semi-glossy finish. When touching it, it shouldn’t feel greasy or sticky.
Why Seasoning Cast Iron Is Important
When we heat oils and fats at high temperatures in a cast iron skillet, they change from a liquid into a hardened, slick surface (otherwise known as polymerization).
Polymerization causes the layer of seasoning to molecularly bond with the iron.
This is because cast iron is, in fact, not completely solid. It’s rough and porous and has a jagged texture that gives the seasoning more surface area to bond with.
So, when we season our pans, the fat layer builds up and slowly sinks into the pores, becoming smooth and non-stick.
Think of it as a puzzle.
The pieces you have are the iron, and the missing parts are for the fat to fill.
Luckily, most skillets come with factory seasoning when you purchase them. If that’s the case, then you don’t need to season your skillet and can immediately start cooking your favorite dishes.
However, if you’ve bought yours second-hand, you’ll need to re-season it to create a hardier non-stick coating. Without a layer of seasoning, cast iron will begin to corrode and rust because of the moisture and oxygen in the air.
What Oil is Best for Seasoning Cast Iron?
Overall, flaxseed oil is the best for seasoning cast iron.
Why? Because each cooking oil has different amounts of polyunsaturated fats. The greater the amount, the more likely it is to oxidize and polymerize.
Flaxseed oil has 68% polyunsaturated fat. This means it oxidates and polymerizes quicker than other oils. We usually find this oil gives us better seasoning results consistently.
Here are some other cooking oils commonly used to season cast iron.
As you can see, flaxseed oil isn’t the only cooking oil you can use when seasoning your cast iron skillet.
Less expensive oils such as sunflower and soybean oil do just as good a job.
In fact, sunflower oil is often recommended by other sources because it’s more affordable and offers similar results.
How To Clean A Cast Iron Skillet
Cleaning plays a massive role in the lifespan of your cast iron skillet and helps protect it from damage. Luckily, you can be rougher with cast iron when you clean it, unlike other materials like Teflon or ceramic.
Let’s get cleaning!
What you’ll need
- Sponge/ Stiff brush
- Paper towels/ clean, dry cloth
- Paper towels
- Kosher Salt (if needed)
- Clean it immediately: Once you’re done cooking, clean your skillet as soon as possible while it’s still warm. Avoid leaving it to soak in the sink as this may cause rusting.
- Use hot water: Always hand-wash your cast iron skillet. Use a stiff brush or sponge when cleaning. Contrary to belief, you can use a little dish soap if you need to remove stubborn food. But avoid putting the skillet in the dishwasher.
- Scrub: If you have stuck-on food, don’t be afraid to be a bit rougher. You can scrub your pan with kosher salt and water to remove any stubborn food. For any stains from acidic ingredients, use boiling water.
- Dry: Once you’re finished cleaning, thoroughly dry it with a clean cloth or dry paper towel. Never drip-dry your cast iron skillet. Once dry, put it on the stove over medium-low heat.
- Add Oil: Like seasoning, apply a light coat (roughly ½ teaspoon) of your preferred cooking oil with a paper towel or cloth. Some cooks like to add oil on the outside too. Buff to ensure there’s an even coat and remove any excess oil. Continue to wipe the surface until your skillet looks dark and smooth.
- Cool & Store: Once your pan is cooled completely, put your skillet in a dry place to help prevent rusting.
Remember: Using dish soap or steel wool on your skillet isn’t the end of the world. But you may find you’ll need to re-season it.
Older well-seasoned skillets can easily cope with a small amount of soap. Just make sure to rinse well, so any residue is removed and oil after it’s dried.
Storing A Cast Iron Skillet
Like cleaning, storing a cast iron skillet correctly is crucial, especially if you want it to last a long time.
It helps prevent any unnecessary scratches or damage that absorb the air’s moisture, leading to rust.
We recommend using a paper towel (or two) to protect your perfectly seasoned skillet. Adding paper towels helps to prevent friction. If you’re tight on space in your kitchen and have to nest cookware pieces inside one another, it’s a great way to add a layer of protection.
You don’t have to change the paper towel every time you use your cast iron pan. Just make sure it’s clean and intact. If your paper towel becomes dirty, swap it for a fresh sheet.
Or, you can use small pieces of cardboard or toilet roll if you need to.
Can you use acidic ingredients in cast iron?
Contrary to what you’ve most likely read online, cooking acidic foods will not cause severe damage to your cast iron skillet.
To measure the acidity of ingredients, you have to consider their pH (Powder of Hydrogen) number. This is determined on a pH scale, ranging from 1 to 14.
Anything below 7 is acidic, such as lemon, honey, or white wine. While anything above 7 is alkaline-based.
Below are some examples of common ingredients and their pH numbers:
- Lemon: pH 2
- Vinegar: pH 2
- Lime: pH 2.8
- White Wine: pH 3
- Red Wine: pH 3.3
- Sauerkraut: pH 3.5
- Pickled Cucumber: pH 3.6
- Honey: pH 3.9
- Tomato: pH 4
- Yogurt: pH 4.4
- Buttermilk: pH 4.5
- Sour Cream: pH 4.6
- Cheese: pH 5.1
- Beef: pH 5.4
- Cocoa: pH 5.6
- White Flour: pH 6
- Chicken: pH 6.3
- Milk: pH 6.7
- Egg: pH 7.6
Herbs and spices also play a part in a dish’s pH level. For example, cinnamon has a 2 pH level and is considered more acidic, while spices like ginger are more alkaline-based.
If you cook acidic ingredients in your cast iron for a long time, tiny metal molecules can transfer to your food. While these molecules leave a horrible metallic taste in your dish, they’re harmless.
Always remove any acidic recipes from your cast iron skillet once you’re done cooking. And always remember to re-season it after use too.
How to Remove Rust from Cast Iron
Over your cast iron skillet’s lifetime, you may find its seasoning becomes dull, or it begins to rust badly.
The most common cause of rust on cast iron is “profile rusting.” This usually happens when it’s exposed to too much moisture. Luckily, profile rusting is easy to remove at home, and you won’t need to throw your skillet away.
What You’ll Need
- Dish soap
- Sponge, scrubbing brush, or scouring pad
- Steel wool
- Paper towels
- Cooking oil
- Aluminum foil
- Remove rust: Use steel wool to remove any rust you see on your skillet. Scour it until the affected areas are raw cast iron.
- Wash: Wash it with warm water and a small amount of dish soap. Scrub the skillet with a scouring pad, sponge, or scrubbing bush if it’s stubborn.
- Dry: Make sure your cast iron skillet is thoroughly dry using paper towels or a clean dishtowel.
- Add oil: Apply a small amount (1-2 teaspoons) of your preferred cooking oil to the entire pan, including the outside and handle. Then, buffer to remove any clumps and prevent stickiness.
- Bake: Place your skillet upside down on the top rack of a 350°F oven. Place a sheet of aluminum foil underneath to catch any drips and keep things clean. Leave for one hour.
- Cool: Once done, turn off the heat and allow your skillet to cool completely before using it again.
If your skillet has severe rust, you might have to strip it back to its raw material.
But don’t give up hope! You can use products like Easy-Off Oven Cleaner, a strong alkali spray that gives your skillet a new lease of life.
A fume-free oven cleaner that we often reach for when there are rust problems for our cast iron skillets. It removes tough grease and food from just about anything!
This spray can also be used to clean ovens, broilers, and even stainless steel surfaces.
Just be sure to wear rubber gloves and work outdoors for better ventilation.
As you’ve probably guessed, owning a cast iron skillet is no easy task.
They have to be seasoned regularly with the right type of oil to prevent sticking. And, cast iron skillets have to be cleaned and stored correctly to avoid damage and rust.
Nonetheless, we can’t rate them highly enough.
We love these skillets for their durability, heat retention, and versatility. You can use them for just about any dish you’re making. And, you can pass them on to the next generation too.
Think of them like a car. If you service them regularly and invest your time looking after them, they’ll keep giving back. But, if you take your foot off the gas and neglect them, they’ll cause you nothing but problems.
We hope this guide on caring for cast iron skillets has been helpful. Let us know your thoughts on them or whether you find them as good as we do!
Hey I'm James, the one who started Purely Cookware. All my life, I've been lucky enough to bond with family around the dinner table. And I will be using this website to teach you how you can do the same.