Seasoning (also called curing) is a process used to prepare cast iron cooking pans for use. Before it can be used for cooking, a cast iron pan must be seasoned in the oven. There are two important reasons why this needs to be done:
The seasoning process for a pan isn't difficult at all. No two people seem to agree on the exact method for seasoning a pan (what oil to use, temperature, waiting time, etc.), so I'll just quickly describe how I seasoned my 12-inch skillet and made it black and non-stick.
One coating of seasoning is enough for you to start cooking with your pan, though if you want to give it a good non-stick seasoning, repeat this process two, three, or even four times: take the pan out of the oven, give it another thin coating of oil, put it back into the oven, heat it to 425, cook it for 60 minutes at 425, and then turn the oven off and cool it again. Give the pan another coating of oil, and repeat.
YouTube has hundreds of homemade videos that demonstrate the method for seasoning a cast iron pan. As mentioned above, no one can agree on the exact specifics of the seasoning – some use vegetable oil, some use fat or bacon grease; some cook the pan in the oven at 350 degrees, while some go as high as 500 degrees or more. Here are a few for starters:
Every genre has its own internal politics and topics for argument, and seasoning a cast iron pan is one of the most talked-about, debated, and argued-over topics among users of cast iron cookware. For example, these days when you talk about seasoning a cast iron pan on the Internet, you will be practically guaranteed to receive a comment like this: "Try this super method of seasoning your pan with flaxseed oil." This is a recent fad that became popular when Cook's Illustrated magazine eagerly endorsed a so-called "science-based" method of seasoning cast iron and declared it to be "the ultimate way to season cast iron." (The article itself, from the January 1, 2011 issue of the magazine, can be read here: ) The tone in which the article supported this method made me suspicious, and in the fall of 2011 I set out myself to apply a scientific test to this method. My conclusion was that flaxseed oil is a decent method for seasoning a cast iron pan, but it doesn't have any advantage over any other method of seasoning. So go ahead and season your cast iron with the method that works best for you, whether this involves using lard, shortening, vegetable oil, or flaxseed oil. And that is an example of the heated arguments that you will find among users of cast iron.
About a month ago, I spent a Saturday morning giving my 12-inch skillet four or five coats of seasoning, and right after that I made a video of myself cooking an egg on it. It didn't stick at all, and the cooked egg fell right out of the pan when I tipped it onto the plate. If you don't want to spend a whole morning or afternoon hanging around at home and waiting for your pan to heat up and cool off, do the seasoning a bit at a time – one hour per night, for instance. Or, after you've seasoned it for the first time, start grilling the hell out of stuff! Cooking greasy meat is also a great way to season your pan, and you'll have a lot of fun doing so.
July 14, 2012: Whew. Today I was finally able to spend a day cleaning up, unpacking, and putting things away after my out-of-state camping trip last weekend. I'd brought along three big cast iron pots – a Lodge 5-quart dutch oven, an 8-quart Best Duty potjie (a South African cast iron pot that looks like a medieval cauldron; it's a lot of fun to have this!), and a huge Bayou Classic 16-quart dutch oven (this one is a monster – 15 inches diameter and 8 inches tall). We put these pots through a lot of use on the camping trip, and as a result the big pots had some wear and tear. The potjie pot had been used to make vegan stew with tomatoes, and as a result there was a thin layer of rust on the inside of the pot. The big dutch oven, meanwhile, had some traces of rust because it had never been heavily seasoned; I'd burned off its initial wax coating (used for shipping) and oiled it before taking it camping, but I hadn't given it a thorough seasoning. So today, as I cleaned house, I took the effort to season these big pots in the manner they deserved.
These pots were so big that I could only season them in the oven one at a time. I prepared for this with a trip to the dollar store (Dollar Tree is a frugal cook's best friend!) for cheap washcloths and sponges. To clean the dutch ovens I used apple cider vinegar, and for the seasoning I used reserved bacon grease – grease that I'd collected in a glass container during previous times I'd cooked bacon. The bacon grease was at room temperature, not heated.
The actual effort of seasoning these pots was simple, but it took a lot of time and effort because the pots were so BIG. It was simply a matter of doing the following:
In the kitchen sink, I added vinegar to the bottom of the potjie (about 1/8 cup), added about a tablespoon of kosher salt (for friction), and gave every inch of the pot a thorough scrubbing with steel wool. I scrubbed inside and out, and the result was a coating of ugly black goo, all over the potjie and the inside of the sink. I then rinsed it all out with water from the sink (I didn't use detergent), poured about 1/8 cup of bacon grease into the potjie, and use a dish cloth to rub it all over every inch of the pot – again, both inside and outside. After this, I used several paper towels to wipe off the inside and outside of the pot. A grease coating for seasoning cast iron doesn't have to be dripping or sticky; all it needs is a thin sheen of a coat in order to season properly. I placed the potjie on the bottom rack of my oven, upside down so that any extra grease would not collect on the bottom of the pot. From there, I did the same thing with the iron lid to the potjie pot: pour on about a tablespoon of vinegar, vigorously scrub every inch with steel wool, rinse it off, apply bacon grease with the cloth, towel it off with paper towels, then placed it on the oven rack alongside the potjie pot.
From there, I closed the oven door, heated the oven to 500 degrees F, and let it cook at 500 degrees F for 60 minutes. Note on heating the pots: be sure to have open windows and fans for ventilation, and take down your smoke detector! This produces some heavy smoke, which will set off your smoke alarm if you're not careful. Also, this should be a standard for everyone but I'll say it just to be sure: DO NOT LEAVE YOUR HOUSE when heating up a big pot to 500 degrees in your oven! This process should be supervised for every moment until the oven has been turned off and the pots cooled down.
After this, I turned the oven off but left the pot in the oven to cool down. After 30 minutes, I used heavy oven mitts to take the pot and lid out of the oven (they were still very hot!) and place them on the stovetop range to cool off some more. After about another 15 minutes, they were still very warm but not burning hot, so I used a separate dishcloth (not the one I'd used with the bacon grease) to apply a thin layer of generic store brand vegetable oil to the pot. I just poured a little oil into the bottom of the pot – I didn't need a lot, maybe only a teaspoon of oil – and used the cloth to wipe every inch of the pot with oil, inside and out. This left the pot shiny and black. From there, I did the same with the lid. Finally, after letting it all cool down, I was able to put the potjie pot in its place, and turn my attention to the huge Bayou Classic dutch oven.
I used the same process on the 16-quart dutch oven that I'd used with the 8-quart potjie pot:
After all this, I thoroughly cleaned the grease out of the sink with dish detergent and dollar store sponges, then threw them out – grease cloths, sponge, and all of the paper towels used to clean the pots. That's why I'd purchased them at the dollar store.
Here are the big pots after seasoning.