Cast Iron Cooking and Care – A How To Guide

Cast iron is more work to clean, it can go rusty, and you need to season it. Why bother?

It is good at cooking, especially stir frying and searing. More importantly it can last several lifetimes if treated well. Would you like your children to cook in the same pot you are using now?

Cast iron cookware is not that much more work and it depends how often you use it. You don’t have to go all in with cast iron. Perhaps start with one pan to begin with, and see if you like it.

Or, if you are wondering why you’ve inherited a rusty old pan – don’t worry! It’s a treasure that you will always be grateful for.

Whatever happens, don’t throw away that old cast iron pan just because it is rusty. It won’t take much to fix it!

Choosing Your Cast Iron Pan

Types of Pans

If you are buying a new cast iron pan and are trying to come to terms with some of the vocabulary here’s a quick guide:

  • A skillet is basically a frying pan. It is versatile and probably the best type of pan to start with.
  • Griddles are large flat pans with little or no lip. They are great for cooking pancakes or large breakfasts.
  • Dutch Ovens are big stock pots with mandatory lids. You can cook up a lovely stew with them. They may have legs to help them stand in a fire.

Features

Pouring Lip

A Lip on a cast iron pan.  The lip bows out slightly from the edge of the pan

It’s always nice to see little pouring lips on the side of the pan. This is often built into the pan. It’s easier to do with cast iron since it can literally be part of the cast, so it doesn’t need extra machining.

Handle

Cast Iron pans should have an integrated handle. This handle is part of the block of cast iron and will get hot when cooking. You will need to use a tea towel to hold it. It also won’t fall off or come loose – a common complaint for other cookware.

Lids

I’m a big fan of see through lids. You can buy these separately and use them with your cast iron pan. If you do that the pan is likely to last much longer than the lid!

cast iron lid with food on it

Or, a cast iron pan or pot with its own solid lid is a real treat, even though you can’t see through it. The lid will last as long as the pan. You can even use the lid as a dish if you are desperate.

Carbon Steel vs Cast Iron

There is little difference in the makeup between carbon steel and cast iron. Both have over 95% iron, with a small amount of carbon. In fact cast iron has more carbon than carbon steel.

You care for both in the same way. All the seasoning and cleaning rules that apply to cast iron also apply to carbon steel. But, you don’t cook with them in the same way – unless you want to burn your food!

The main, root, difference is that carbon steel is softer and more malleable. This means that it is pressed into the shape needed. Cast iron is melted and poured into a cast (it’s literally cast iron).

As it is pressed instead of cast, carbon steel is much thinner. This means that the main practical differences between cast iron and carbon steel are:

  • Cast iron cookware is heavier than carbon steel (nearly twice as heavy for the same size pan)
  • Carbon steel cookware is quicker to warm up cast iron.
  • Cast iron pots and pans retain their heat for longer than carbon steel pans

Cooking Differences

So, from a cooking perspective the differences between carbon steel and cast iron are:

  • A cast iron surface won’t be cooled by food easily, so it’s great for stir frying, searing and grilling. You can get nice crispy brown veg and meat with a cast iron pan, but it’s easier to burn food.
  • Carbon steel surfaces are cooled when adding food. This means food is less likely to be burnt or crisped in carbon steel cookware. It also makes carbon steel ideal for cooking delicate food.

Machine Oil

Cast Iron or Carbon Steel can come covered in machine oil. This oil protects the metal whilst it is on its way to you. If it isn’t pre-seasoned it should be covered in machine oil.

It does seem that carbon steel is more likely to arrive covered in machine oil than cast iron.

You must watch out for this. The pan will appear to be oily and dirty. This oil is not something you want to eat. You must clean it off and then season the pan straight away.

Smoothness

Carbon steel pans are smoother than new cast iron pans. This is because the cast ( made of sand) will have a textured surface.

Although a smoother surface is less sticky, it isn’t a big deal. You can sand the cast iron to a smooth surface yourself if you want.

It seems like quite a lot of work to me though. I don’t even own a sander! The work doesn’t stop there as it is likely that it will be harder to season.

There is an alternative though – buy or acquire an old pan, ideally pre 1940’s. In the past manufacturers used to polish the pan themselves after the casting. An old pan should already be seasoned so you save even more time.

Seasoning Your Cast Iron

Always clean and season a new cast iron pan. I recommend flaxseed oil, but the most important thing is that the oil has to be pure. Seasoning is easy but takes time. You should:

  • Clean your cast iron pan
  • Completely dry it (on stove or oven)
  • Apply pure food grade oil all over, including outside and handles
  • Heat the cast iron pan until the oil smokes

Repeat this as many times as you like. For more details, check out my guide to seasoning cast iron cookware.

Cooking With Cast Iron

Cooking with cast iron is not the same as cooking with Teflon or stainless steel. When I first started, I burnt my food all the time. It’s not harder. It’s not easier. It’s different, and when something is different you need to learn how to do it again.

Cast Iron takes longer to warm up

Remember the cast iron will take a longer time to warm up. It’s also only nonstick when pre-warmed. This means that you need to wait longer before popping food on it. You could start warming the pan whilst you are still preparing the food for it.

Another reason to take longer warming up the cast iron is it will help avoid hotspots. Cast iron doesn’t heat evenly if it is still warming up.

You know the cast iron is ready by putting your hand over it. You can feel the heat coming off a warm pan. Cast iron pans are better at radiating heat than other cookware. 

What heat to use

Go for a lower heat than you normally would. If you would use a high heat, use medium. If you usually use a medium heat, go low.

Cast iron cookware is very efficient once warmed up. If you go too high you will burn your food, so it’s best to go a bit low to begin with. Eventually you will get the feel for it and it will be instinctual.

When to use it

You can use cast iron for cooking pretty much anything. That said, it’s probably most effective at:

  • Searing meat
  • Stir frying
  • Anything where you are trying to get a crunchy brown exterior

How to cook with cast iron

Utensils

Wood, plastic and silicone utensils are always going to treat any surface better than metal. Metal can scratch.

A Metal utensil resting in a cast iron pan

With cast iron, once it has the seasoning, you should be able to use metal utensils. In fact the metal utensils may be useful for scraping off food. Try to be careful not to scratch off the seasoning. If that does happen – no problem, just re-season.

Acidic Foods

Acids and metals react. Since cast iron isn’t as protected as stainless steel or nonstick, acidic foods will dissolve it.

It does have some protection, though – the seasoning layers you built up. This won’t stop all of the acid reaching the iron though so you need to be careful.

You can occasionally use cast iron with acidic foods. Try to minimise the amount and make sure you clean it straight after.

Examples of foods with high acidity are:

  • Tomatoes
  • Vinegar
  • Citrus fruit
  • Alcohol
A picture of some tomatoes

By the way this isn’t the same as acidic foods you would avoid on an alkaline diet. Some food is acidic once inside your body (it changes). Meat is a good example of this. Meat is fine for cast iron, but avoid it if on the alkaline diet.

Oil

Always cook with oil when using cast iron cookware. It helps make the pan nonstick, and protects it from water. It may even add to the seasoning in the long term..

Which oil isn’t important, though some oils are healthier than others. Make sure you are using an oil with a high enough smoke point.

Cast Iron Griddle

Since griddles are larger you may need to position it over two burners. You definitely need to move it occasionally to heat the whole surface.

Cast Iron Skillets and Frying Pans

When you are frying with cast iron do it on a low heat. It can actually be less work as you shouldn’t need to turn over the food as often. lf you are struggling to get the food to release it may not be ready to turn over yet.

Cast Iron Dutch Oven

Two cast iron dutch ovens with lids sitting on a fire

Dutch ovens are often used outside on fires. They can be a great camping tool. Smaller ones may be suitable for the stove top as well. If they have legs then they will probably only work on a gas stove or a campfire.

Cast iron dutch ovens are very versatile, you can use them for:

  • Baking bread
  • Roasting chicken
  • Cooking pot roast
  • Preparing Chilli

Cleaning Cast Iron

Cast Iron isn’t difficult to clean but you can’t just pop it in the dishwasher or leave it to soak.

The first rule when cleaning cast iron is minimising the time spent in water or wet. Clean it straight away, whilst it is still warm.

The second rule is to not put cold water in a hot pan. It will crack – like glass. Try to use the same temperature water as the pan.

I’ve prepared a detailed guide to make sure you get it right, but the main steps are:

  • Scrap and rinse you cast iron pan.
  • Give it a light scrub with as little soap as possible.
  • Dry your cast iron pan using an oven or a stove
  • Lightly oil the cast iron surface all over

Dishwashers

Ok I’ll admit it, I’m one of the first people to throw things in the dishwasher that I probably shouldn’t have done. Not cast iron though. The dishwasher has harsh detergents, and keeps everything wet for longer. It will strip away the seasoning and start to rust your cast iron. Not good.

Storing Cast Iron

Before you store it, clean and lightly oil it. You should use a long term food safe oil, like sunflower oil.

If you will be storing the cast iron for the long term, heat the pan after oiling until the oil starts to smoke slightly. This will help stop it turning rancid.

When you’re ready to store it, put a paper towel on the bottom to catch any moisture. Then leave it in a dry place with the lid off.

Caring for the whole cast iron pan

It’s important when cleaning and seasoning cast iron to make sure you deal with the whole pan. It is one block of cast iron, so if rust gets to one part it can affect, and even travel to, other parts.

You need to clean, season and oil the:

  • Inside
  • Outside
  • Handle
  • Edges
  • Any nooks and crannies even if difficult to get at

What If It Goes Wrong?

Sometimes things can go wrong – they are often but not always fixable.

Rusty Cast Iron Cookware

Rusty Cast Iron Cookware is completely fixable. Follow my guide to restoring rusty cast iron.

In fact an old rusty cast iron pan is probably a genuine rough diamond. It’s something with real history that will last a long time. You may even find it is of higher quality than modern pans, especially if it has a smooth surface.

Food is sticking to your cast iron pan

If food is sticking to your pan, first consider if you are using it properly:

  • Put your hand over the pan. Can you feel the heat come off it before you put food in?
  • Are you drizzling a bit of oil onto the pan before cooking?
  • Does it have burnt food on it? (Give it a good clean)
  • Are your expectations realistic? Cast iron is nonstick if heated, but it isn’t Teflon!

If you still are finding everything is sticking, you could try cleaning it and then seasoning it a few times.

Cast Iron Flaking

What do you do if the seasoning starts flaking off your cast iron cookware? Firstly it’s probably not seasoning.

Seasoning should be a micro layer, it doesn’t really flake.

There is a good chance it is carbon, i.e. burnt food, coming off. This means the pan needs a good cleaning. Clean it more thoroughly than usual, scrub with detergent or soap, and scrub hard.

burnt piece of food

If you are worried about the seasoning, or got carried away with the cleaning, then season it again.

Cracked and Warped Cast Iron Pans

Whilst this isn’t ideal if the cracking or warping is minor then it should still be useable. There isn’t anything you can do about it though. 

If stuff leaks through the cracks, try re-seasoning it.

Warped cast iron may not be usable on induction or electric stoves but should work on gas stoves. You may need to adjust your cooking around the warping.

Fire or Heat Damaged Cast Iron Cookware

You can see this if the cookware is red, redder than rust that is. There isn’t a lot you can do. Try to use it, or sand down the damage but the cookware may be a gonner.

Split Cast Iron Pans

If the cast iron pan is actually split into two, or more, pieces then it is completely broken. There’s nothing you can do. Throw it away – it’s trash.

Conclusion

Cast iron is a beautiful, durable material that you can use to cook well. It is more work than nonstick, or even stainless steel, so consider carefully if you want to use it.

I like to mix and match. Cast iron takes more time, so I use it less, but I do use it for stir frying and searing.

The first step is to buy / borrow / acquire a cast iron pan and see if you like it. Give it a try!

Share this post

Share on facebook
Share on twitter
Share on linkedin
Share on email
Share on print