Seasoning is the process that transforms raw cast iron into the legendary cooking surface that cast iron enthusiasts rave about. A well-seasoned pan offers natural non-stick properties, protects against rust, and develops a beautiful patina that improves with every use. Whether you have a brand-new pan that needs its first seasoning or you are restoring the seasoning on an older piece, this comprehensive guide will walk you through everything you need to know.
Understanding What Seasoning Actually Is
Before we dive into the how-to, it helps to understand what seasoning actually means in the context of cast iron. Seasoning is not simply oiling your pan or adding flavour to the cooking surface. Instead, it refers to a layer of polymerised oil that has bonded to the iron at a molecular level through a process called polymerisation.
When oil is heated past its smoke point in the presence of iron, the fatty acids in the oil break down and reorganise into a hard, plastic-like coating. This coating fills in the microscopic pores and irregularities in the cast iron surface, creating a smooth, non-stick layer. Over time, with proper use and care, this layer builds up and becomes increasingly effective and durable.
Seasoning is not a one-time event but an ongoing process. Every time you cook with oil in your cast iron, you are adding to and reinforcing the seasoning layer. This is why well-used cast iron pans often have the best non-stick properties.
What You Will Need
Gathering the right supplies before you begin will make the process much smoother. Here is what you will need:
- Your cast iron pan - Clean and completely dry
- High smoke-point oil - Flaxseed, grapeseed, vegetable, or rice bran oil work well
- Paper towels or lint-free cloths - For applying and wiping oil
- Oven - Capable of reaching at least 230°C (450°F)
- Aluminium foil - To catch any drips (optional)
- Oven mitts - Cast iron gets extremely hot
Choosing the Right Oil
The oil you choose for seasoning matters more than many people realise. Different oils have different smoke points and fatty acid compositions, which affect how well they polymerise and how durable the resulting seasoning will be.
Recommended Oils for Seasoning
Flaxseed oil has gained popularity as a seasoning oil because it forms a very hard finish due to its high concentration of omega-3 fatty acids. However, it can be finicky and may flake if not applied correctly. It also has a lower smoke point, requiring careful temperature control.
Rice bran oil is an excellent choice that is readily available in Australia. It has a high smoke point of around 254°C and creates a durable, smooth finish. Many Australian cast iron enthusiasts swear by this option.
Grapeseed oil is another solid choice with a high smoke point and neutral flavour. It polymerises well and is affordable and widely available.
Vegetable or canola oil are budget-friendly options that work perfectly well for seasoning. While they may not create quite as hard a finish as flaxseed, they are forgiving and produce excellent results for everyday cooking.
Avoid using butter, olive oil, or coconut oil for oven seasoning. These have low smoke points and can leave a sticky residue rather than a proper polymerised layer. Save these oils for cooking once your pan is well-seasoned.
Step-by-Step Seasoning Process
Step 1: Clean Your Pan Thoroughly
If your pan is new, wash it with warm water and a small amount of dish soap to remove any manufacturing residue or protective coating. For older pans, make sure all food residue and old flaky seasoning is removed. Dry the pan completely, ideally by placing it on a low burner for a few minutes to evaporate all moisture.
Step 2: Apply a Thin Layer of Oil
Pour a small amount of oil onto a paper towel and rub it all over the pan, inside and out, including the handle and bottom. Then, using a clean paper towel, wipe off as much oil as you possibly can. The pan should look almost dry. This is crucial because excess oil will result in a sticky, uneven finish.
Step 3: Heat the Pan in the Oven
Place your pan upside down in a cold oven, with aluminium foil on the rack below to catch any drips. Set the oven to 230°C (450°F) and let it preheat with the pan inside. Once it reaches temperature, let the pan bake for one hour.
Step 4: Cool Completely
After one hour, turn off the oven and leave the pan inside to cool completely. This gradual cooling helps the seasoning bond properly to the iron. Removing a hot pan and exposing it to cool air can cause the seasoning to crack.
Step 5: Repeat for Best Results
For a new pan or one that has been stripped, we recommend repeating this process three to four times. Each layer builds upon the last, creating a more robust and effective non-stick surface. With each repetition, you will notice the pan taking on a darker, more lustrous appearance.
The most common mistake in seasoning is using too much oil. A thick layer of oil will not polymerise properly and will remain sticky or gummy. After applying oil, wipe the pan until it appears almost dry. If in doubt, wipe it again.
Maintaining Your Seasoning
Once you have built up a good base of seasoning, maintaining it is straightforward. Here are the key practices to keep your seasoning in top condition:
- Cook with oil regularly - Every time you cook with oil, you reinforce the seasoning
- Avoid prolonged soaking - Water is the enemy of seasoning; clean promptly and dry thoroughly
- Store properly - Keep in a dry place with a light coating of oil if stored for extended periods
- Use appropriate utensils - Metal utensils are fine, but avoid sharp edges that could scratch
- Re-season as needed - If you notice food starting to stick or dull spots appearing, it is time for a fresh seasoning layer
Troubleshooting Common Issues
Sticky or Tacky Surface
This typically results from using too much oil or not heating the pan hot enough. To fix it, place the pan in a very hot oven (260°C/500°F) for an hour to help the oil fully polymerise. For severe cases, you may need to strip the seasoning and start fresh.
Flaking Seasoning
Flaking can occur when seasoning layers are applied too thickly or when incompatible oils are used. Strip the affected area by scrubbing with salt and oil, then re-season with thin layers of a high smoke-point oil.
Rust Spots
If rust appears, do not panic. Scrub the rust away with steel wool, wash and dry the pan, and immediately apply a fresh layer of seasoning. See our restoration guide for detailed instructions on dealing with rust.
Australian Climate Considerations
Australia's varied climate can affect how you approach cast iron care. In humid coastal areas like Queensland or coastal New South Wales, rust can develop more quickly on poorly-seasoned pans. Consider storing your cast iron with a thin layer of oil and ensure thorough drying after every wash.
In drier climates like inland South Australia or the Northern Territory, the risk of rust is lower, but the dry air can sometimes cause seasoning to appear dull. This is purely cosmetic and does not affect performance.
If you live in a humid area, consider storing your cast iron in the oven (when not in use) where the residual heat from the pilot light or last use helps keep moisture at bay. Alternatively, store with a paper towel inside to absorb any moisture.
Final Thoughts
Seasoning your cast iron pan is a simple process that rewards patience and attention to detail. The key principles to remember are: use thin layers of oil, heat past the smoke point, and allow proper cooling. With these fundamentals mastered, you will build a cooking surface that rivals any modern non-stick pan while offering durability measured in generations rather than years.
Remember, seasoning improves with use. The best thing you can do for your cast iron is to cook with it regularly. Each cooking session adds to the seasoning, creating a pan that truly becomes better with age. Welcome to the satisfying world of cast iron cooking.