With proper care, these inexpensive pans will become treasured heirlooms. And it really isn’t all that tricky to maintain them. The prime directive for these pans is, never, ever use soap to clean them. I know it probably sounds icky, but you should never use soap on a seasoned cast iron pan. The stuff that makes a cast iron pan seasoned is oil, and soap breaks down oil. So soap goes against everything you’re trying to accomplish here.
Ok, so the real first step is to buy a pan. If you want to streamline this process, you have two options — option one is to buy a used pan in an antique store, or on ebay. Chances are, you’ll end up paying about 3 times what you would spend for a new pan, but you’ll be getting the fine, aged, slick surface that someone’s grandma spent 20 or more years to create. (You might also luck out and find a deal at a yard sale.) Your other option is to go for a factory-installed pre-seasoning. Lodge puts out a whole line of pre-seasoned pans. They’re not perfect, but they’re a good start — saving you a few months on the long journey to seasoned bliss.
So here’s the process you probably want to start even with a pre-seasoned pan, but especially a new, unseasoned pan, or a pan that has been mishandled and shows signs of rust, or that has a layer of grody goop. Thoroughly wash your new pan, getting off any debris or gunk. (It’s actually ok to use soap here if your pan is really dirty.) Turn your oven on to 375°, and put a sheet pan on the lower rack. Put the pan in the cold but warming oven, and let it preheat and then bake for a while. At least half-an-hour, but an hour is better. Carefully remove the pan with pot-holders and move it to your stove top. Crack a window and turn on the exhaust fan, then pour a couple teaspoons of canola oil into the pan, and using a thick wad of paper towels, spread the oil all over the inside of the pan, and up over the edge, and even the outside, being extra careful not to burn yourself. (Seems stupid to do it on the outside of the pan, but one of the reasons for doing all this is to add a protective layer onto the metal and keep it from rusting on you.) Return the pan to the oven, upside down over the sheet pan, and repeat this process, a couple more times, as many as you can handle. Early in the life of the pan, you’ll end up with a thick, shiny layer of oil on the pan, sort of like urethane on wood. Eventually, with heating, this layer will cut back and form a matte black, slick finish. If your pan ever gets mistreated, rusty, or otherwise, repeat this process. (I inherited a huge cast iron frying pan from my grandmother, and it had a thick, spongy layer of black goo completely covering it. I lit up my charcoal grill and put the pan in there, lid on, and walked away. 3 hours later, the 80-year old pan emerged pristine and good as new, ready for its first layers of oil.)
So, once you’ve got this pan going, what next? Well, use it. It won’t be perfectly non-stick at this point, and will probably require a little more elbow grease to clean it, but you need to repeatedly heat it and cook the seasoning. These early days, it’s probably a bad idea to cook anything acidic, like chili, tomato sauce, or deglazing with balsamic. If you do, your food will end up tasting sort of nasty. It’ll have a distinct metallic taste. (In general, acidic foods in cast iron is never a great idea, but you can get away with it once in awhile, once the seasoning has matured.)
So now you’ve cooked with it. Now what? Ok, you want to rinse it with hot water and a stiff sink brush, or even a plastic scrubby sponge. No soap. Never soap. Also, never let the pan soak in water. Once you get most of the food off, you want to dry the pan. Do this by putting it back onto the stove over high heat. Whats left of the water will fizzle away. As the pan gets hotter and hotter, whats left of the fragments of food will burn away, too. I usually let the pan sit on the stove until I smell it. Then, turn the heat off, and apply a new layer of oil. For this, you can use the canola and paper towel method, but what I do is spray the pan with a canola oil non-aerosol spray. (Trader Joes sells the stuff for, like, $2.50 a can, which will last you for months.) Just a thin layer, and since the pan is hot, it’ll probably smoke a little. That’s ok. Let the pan sit on the stove and cool completely.
Remember that cast iron is pretty brittle. If you drop it, provided you don’t break a toe, the pan could shatter. (The unfortunate demise of my grandmother’s heirloom.) Also, these steps can be used on french steel pans, too, which are just as inexpensive as cast iron, but they don’t have the mass, so they’re not as good at providing even heating… much better for a fast sauté. (French Steel, sometimes known as “blue steel” pans can be purchased mail-order or through restaurant supply stores, and you can get a 10″ pan for about $20.)
These methods apply to any cast iron pan shape you can think of. I recommend the 10″ and the 15″ pre-seasoned pans, as well as the reversible griddle/grill pan. I don’t recommend a cast iron dutch oven, unless you can’t afford to get an enameled one, since you’ll probably want to use the dutch oven for those acidic foods I mentioned before, and it’s just not worth the risk of ruining the flavor with the strong flavor of metal.