Kitchen Tip Tuesday – Try Flaxseed Oil for Re-seasoning Cast Iron

I love cooking with cast iron. Guess I’m just old school. Recently, I noticed my skillets and Dutch oven needed re-seasoning. Previously, I’d used vegetable oil to season them. This time, I decided to use flaxseed oil after reading a Cooks Illustrated article. They tried it in their test kitchen and came away impressed with the result.

Seasoning with flaxseed oil is a weekend chore as it takes a couple of days to complete. The majority of that is hands-off time when your cast-iron cookware is in the oven for several hours. But you’ll repeat the process five times to get the hard, seasoned finish you want. Make sure to use a quality 100% flaxseed oil. I used a Whole Foods house brand. Flaxseed oil is more expensive than vegetable oil, but the durable foundation it builds stands up to repeated use and cleaning and is worth it.

First, strip off the old seasoned finish. By far the easiest way to do this is to place the cast iron inside the oven on its racks and use the oven’s self-cleaning option. My oven’s self-cleaning option takes three hours. The result was amazing! All the old, uneven and pitted areas that had built up on the cookware were gone, leaving rust dust and the original gun-metal gray color of a new, unseasoned skillet. Scrub and rinse it clean with hot water.
Next, dry and heat the iron back in the oven set at 200 F for 20 minutes.
Now you’re ready to work the flaxseed oil into it. Carefully remove the hot cast iron from the oven. (I used heat resistant gloves to do this.) And with a couple of thickly folded paper towel sheets, rub a teaspoon or so of the oil onto the surface of each piece of cast iron. Wipe off any excess.
Place the cookware upside down on the racks in a 500 F oven. After 1 hour, turn the oven off, allowing the cookware to slowly cool in the closed oven for 2 hours. Repeat the process another four times or until a fine hard black surface develops.

It’s a dirty job. But once cleaned of old seasoning, this cast-iron skillet takes on its original gun-metal gray look.

Don’t be fooled into thinking the surface is as slick as a non-stick skillet. It’s not. However, the flaxseed oil foundation is incredibly durable. Where I once found myself frequently having to re-season my vegetable-oil based skillets, I no longer have to do that. The cast iron cleans exceptionally well and holds its seasoning. I still use a spray vegetable oil before cooking, and the iron cleans well with just hot water and a stiff brush.

The before and after of re-seasoned cast iron using flaxseed oil. Try it. You won’t be disappointed.

Text and photos by Gregg Patterson