A Guide to Cast Iron, Carbon Steel & Spun Iron Pans
Cast iron, carbon steel, and spun iron pans are all iron pans. In fact, carbon steel has a higher iron content than cast iron and spun iron. Confusing? We know. That’s why we put together this guide.
We’ll walk you through the differences between the three, detailing their relative advantages and disadvantages, so you can decide which material best suits your needs. But first…
Why Cast Iron, Carbon Steel or Spun Iron?
The allure of cast iron, carbon steel, and spun iron pans comes down to three factors: heat retention, durability, and a ‘patina’ that develops over time to make their surfaces release food with minimal sticking.*
- Heat Retention: These pans get very, very hot, and retain that high level of heat during cooking. This translates to superior browning, searing, and crisping up of food, and it is the number one reason home cooks invest in one. Think steaks (beef, tuna or tofu), charred Brussels sprouts, and snappy stir-fries.
- Durability: These pans are robust by nature—that’s why they can go directly on the flames of a barbecue or campfire. All three are heavier to lift than a copper, stainless steel or non-stick pan, which is a sign of their robust construction. They last a lifetime, and can be passed down through generations. Even an old, rusty pan can be revived to perfect condition with a good seasoning session. Speaking of…
- Patina: Also known as seasoning, the patina of a cast iron, carbon steel, or spun iron pan is a layer of polymerised fat. Here’s how the Lodge Cast Iron website describes polymerisation: ‘When oils or fats are heated at a high enough temperature, they change from a wet liquid into a slick, hardened surface. This reaction creates a layer of seasoning that is molecularly bonded to the iron.’ That layer, or patina, is what allows these pans to easily release food. While it won’t be as slick as a non-stick pan—unless the patina is very, very strong—this more natural, traditional method comes close.
*This article talks about raw cast iron pans, not enamelled cast iron pans, which do not build a patina over time because the enamel acts as the cooking surface. We carry enamelled cast iron cookware from Staub and Tramontina.
A perfect seasoned carbon steel pan, like the De Buyer Mineral B Frying Pan (above), will change colour from grey to black when the patina has become stick-resistant.
Maintenance (How to Clean After Each Use)
To reap the benefits described above, you have to put a bit of extra effort into cleaning and maintenance. (It is worth it!) This is because you should not use washing-up liquid or metal scouring pads to a clean cast iron, carbon steel, or spun iron pan. It will wear down the patina, as well as cause the pan to rust. You absolutely should not put them in the dishwasher.
The best way to clean each one of these pans after each use is a two-step process:
- Step 1: Clean the food off your pan by heating it on the hob until it is hot. Then run very warm or hot water from the sink over it (be careful of the steam). Wipe it clean with a soft brush, cloth or soap-free sponge. For stuck-on bits, a paste of bicarbonate of soda and water is a great substitute for washing-up liquid; just make sure not to scrub with a harsh scourer. Wipe dry with a tea towel.
- Step 2: Return the pan to the hob over medium heat. Wait until the sides of the pan get hot, then add a very small amount of neutral oil and rub it all over the base with cloth or kitchen roll. Make sure the oil is completely thin and invisible—an excess of oil will cause sticky blotches to form. Keep wiping until it looks like there is no oil left. Increase the heat to medium-high and leave on the burner for a few moments, until you see a little bit of smoke. Then turn off the burner, let the pan cool, and store it in a dry place.
Seasoning (Prior to Use or to Boost Patina)
While carbon steel pans must be seasoned prior to use (more details in ‘Carbon Steel’ section below), cast iron and spun iron pans come pre-seasoned. However, we recommend seasoning cast iron and spun iron pans before use as well—it kickstarts the patina and makes clean-up easier than if you just started cooking on these pans straight out of the box. We also recommend seasoning anytime you feel the pan could use a boost, or is looking dull. It will bring it back to good shape.
You can season a pan on the hob or in the oven, depending on the material. Below, we’ve noted the best way to season each type of pan.
Cast iron pans, like the Lodge Chef Collection Skillet (above), work just as well in the oven as they do on the hob.
Cast Iron Pans
Cast iron cookware is most popular in the United States, which is where the two cast iron brands we carry—Lodge and Finex—are made. It is made by pouring molten iron into pre-shaped pan moulds. While Lodge handles are typically part of the mould, Finex handles, made of stainless steel, are securely attached to the base with rivets.
While styles of cast iron pans vary, for the most part, they are thick and black. The most classic piece of cast iron cookware is the skillet, essentially a frying pan with straighter sides (for more surface area) and shorter handles.
More than carbon steel and spun iron, cast iron cookware is designed for equal use on the hob and in the oven. That’s why you’ll often see cast iron skillets used for pies, crumbles, and ‘skillet lasagnas’. You’ll notice the shape of a skillet is not particularly well-suited to lifting and shaking. This material has the widest range of tools, from skillets to ridged grill pans, as well as ‘combi cookers’ that are perfect for homemade bread.
How to Season Before Use: Because Lodge and Finex cast iron pans are completely oven-safe, we recommend seasoning them in the oven for the most hands-off experience.
- Preheat the oven to 250°C/230°C fan.
- If your pan is new, skip this step. If your pan is rusty or tarnished, scrub off the buildup with soap, water and a sponge. It is okay in this case because you are re-seasoning.
- Pour a small amount of high-smoking neutral oil into the pan, no bigger than a coin. Rub all over the base, exteriors and handle. Be careful not to use too much, and remove as much excess oil as possible, to avoid sticky patches.
- Place the pan upside down in the oven and ‘bake’ for 1 hour. Allow the pan to cool before storing.
Pros: It is completely oven-compatible. It comes pre-seasoned, so it is not required that you season it before use. However, we recommend doing so, especially because seasoning these pans is easy and mostly hands-off. It is excellent for cooks who enjoy baking. The colour of these pans, as long as rust does not form, is uniformly black.
Cons: Due to its thicker body, it is not as heat responsive as carbon steel or spun iron. Its shape, with short handles and straight sides, is not as easy to manoeuvre around the hob.
De Buyer Mineral B pans must be seasoned before use to remove the protective beeswax coating.
Carbon Steel Pans
Carbon steel is made differently from cast iron. Instead of the material being poured into pre-shaped moulds, it is built in two separate parts: pan and handle. To make the pan’s base, sheets of metal are pounded into shape, and handles are attached to the base with rivets. This is similar to how traditional frying pans are made.
Carbon steel is used more often in France, where our favourite carbon steel frying pan (De Buyer Mineral B) is made. Carbon steel has also been used in China for centuries, where it is the traditional material for woks.
How to Season Before Each Use: Carbon steel pans must be seasoned before each use, especially the De Buyer Mineral B range, which is coated with beeswax to prevent damage during transport. Alex Pole carbon steel pans do not need to be seasoned prior to use, as there is no beeswax coating – you can use them as you would a normal pan, or follow the instructions for Cast Iron above if you want to kickstart the patina.
- Rinse the pan with warm water, soap, and both sides of the sponge to remove any coating. Towel dry and place over low heat to finish drying.
- Add 1/3 cup high-burning neutral oil, 2/3 cup salt, and peels from two potatoes (which helps pull any remaining impurities from the pan’s surface). Reduce the amount of these ingredients for a smaller pan size.
- Increase the heat to medium and cook the salt and potato peels for 8 to 10 minutes, using tongs to spread the peels and salt all over the pan, up to the rim. The pan will turn brown as you keep doing this. You may want to open a window and turn on the exhaust fan, as there will be smoke.
- Discard the contents, allow the pan to cool, and clean with water and a towel. Your pan is now ready to cook. As you use it more, and clean it as specified in the Maintenance section (above) after each use, this pan will go from grey to brown to black, black indicating a perfect patina.
We’ve found this method, which we got from Cooks Illustrated, to be the best. But if you are not keen on using as much oil or salt, or don’t have potatoes, you can try adding a small amount of oil to a hot, clean pan and rubbing it all over so there is no excess oil visible on the surface. Heat until the pan smokes, turn off the heat, wash with warm water, and repeat a few more times until the colour has changed from grey to brown.
Pros: It is more heat-responsive than cast iron, and due to its thinner construction and shape, easier to lift and manoeuvre. Because the colour changes from grey (not seasoned) to brown (on its way) to black (perfectly seasoned) over time, you have a visual cue to how strong the patina is. While some cooks prefer a uniform colour, just as many cooks prefer seeing their pan transform before their eyes.
Cons: Carbon steel pans must be seasoned before use. The De Buyer Mineral B pan cannot be placed in the oven for over 10 minutes, at a maximum temperature of 200°C/180°C fan. Our carbon steel woks, which have wooden handles, cannot be used in the oven at all.
Based in Shropshire, Netherton Foundry pans are 'spun' into shape on a lathe. They have a wide range of cookware, bakeware and accessories.
Spun Iron Pans
You don’t see ‘spun iron’ as often as you see cast iron or carbon steel, and that’s because it is unique to Netherton Foundry. Based in Shropshire, Netherton Foundry draws from the region’s rich heritage of ironmongery. The material is called ‘spun iron’ because sheets of iron are spun on a lathe to achieve their shapes.
Netherton Foundry has a wide range of cookware, from their cult classic Prospector Pan—perfect for oven-to-table dining—to smaller accessories like their Tortilla Press.
How to Season Before Each Use: You can use either method from above, oven or hob, to season a Netherton Foundry pan, depending on whether it is compatible with the oven. The Prospector Pan can be seasoned in the oven, for example, but the Frying Pan, which has a wooden handle, is not oven-safe, and should be seasoned on the hob.
Pros: Netherton Foundry pans have excellent heat-responsiveness and are easy to manoeuvre. Every pan comes pre-seasoned, so seasoning is not required before first use, though we recommend it. They have a uniform black colour. They are made right here in the UK.
Cons: Not all Netherton Foundry pieces are oven-safe; check before use. Due to the relative thinness of spun iron material, exercise caution when using these pans on induction hobs—gradually increase heat when cooking and never, ever use the ‘boost’ function.