Here is achapler from my book that I hand out when I teach a class on dutch oven cooking!
What is seasoning?
Seasoning is the method of preparing the cast-iron cookware for use. Seasoning is an easy but very important first step when using cast-iron. When we season a cast-iron pot, you are preventing rust and providing the cookware with a natural nonstick surface. The surface of cast iron is very porous, like a very fine sponge. The idea of seasoning is to fill all the fine holes with cooking oil, and then to convert that oil, to carbon, with heat. The carbon will eventually fill up all the fine holes and create that natural, renewable semi-permanent nonstick cooking surface. Unlike synthetically coated cookware, cast-iron can be seasoned, re-seasoned, and its cooking surface restored. Remember: Seasoning takes some time and use before a pan develops the shiny, black surface like your grandmother痴 cast-iron cookware. A black, shiny skillet or pot is a well-seasoned skillet or Dutch oven.
Seasoning, Curing, or Oiling your Cast Iron Dutch oven
Never Season your Dutch oven inside (at least while you wife is at home) because of the smoke, smell, and if you go real heavy on the grease or oil, there is a slight possibility of a fire!!!
All Dutch Ovens have a protective edible wax coating to prevent rust while shipping except the old used ones and it is long gone by now!.. To get rid of this material, remove any paper labels and wash the oven with hot, slightly soapy water and elbow grease. Note, always add the soap to the water not the water to the soap! It won't be so obvious that you washed anything off, but you did. Thoroughly rinse all the slightly soapy water out, and towel dry. Now place the Dutch oven upside down, and lid right side up on a heat source, (BBQ grill, outdoor smoker, or indoor oven, remember WIFE BE GONE), at a temperature of 500+ degrees to burn off the wax and be sure to place an edged cookie sheet, or foil on the shelf underneath to catch the drippings... This will remove the protective wax coating. Now allow it to completely cool down. Wash with plain water and dry thoroughly to eliminate any deposits. You can put a light coating of oil on the oven even before it becomes dry. Cast iron is very sensitive to changes in temperature, making it an excellent cooking material, but also making it susceptible to rust if not properly cared for. The oven must be seasoned immediately, or it will start to rust right before your eyes.
The following procedure can be done in your kitchen oven at home. You might want to be sure the vent fans are on, and maybe open a kitchen window or two, cause the carbonizing oil might create an odor in the house. Place the Dutch oven in the oven and when they are just too hot to touch with the bare hand, remove from the heat using gloves. Thoroughly coat them inside and out, the legs, lid, and top handle (even the bottom) with solid Crisco or a vegetable oil. Use a paper towel or a natural fiber brush, not plastic, cause it will melt. Doing this is messy, so do it on some newspapers. Let them cool about 30 minutes, and then wipe the excess Crisco out with a paper towel. The heating process dries the cast iron and also drives out air from the small pores. When coated while hot, and then allowed to cool, the oil gets drawn into these pores.
Lightly grease the inside and outside of the pot and lid including the handles and legs with solid Crisco or a vegetable oil, one that offers a low burning point.
Note if you plan on cooking for groups you might want to stay away from allergenic type oils like peanut oil, ect.
You do not want the oil to pool anywhere while you are seasoning your oven, so be sure to turn the pots bottom, upside down and the lid, right side up. You might put the Dutch oven in upside down, and then put the lid on the top of the legs. Be sure the cookie sheet or foil is still on the shelf underneath to catch the drippings. You want the heat to go to around 400 to 425 degrees to heat the oil. You will notice that sometime/all times during this process, a slight smoke will come out for about 20 minutes or so. This is normal. Remember, you are carbonizing the oil into the pan. That is what creates the nice black look that you want. Your Dutch oven will be extremely hot!!! After 1 ｽ hours, just turn the heat off and let the Dutch oven cool inside the oven by itself. This will take some time. I just let mine sit overnight, and that way it is cool in the morning when I take it out. Your oven should be a nice black color. If you get what I call dappling, this is from not removing all of the protective coating before seasoning your Dutch oven. All you need to do is re-scrub those areas and then re-season your Dutch oven. If it is a brown or bronze color, then you need the temperature higher, and/or a longer time cooking. If the pans are not as black as you like, just put on another light coat of oil and repeat the heating process on a little higher heat. Remember, you want your Dutch Ovens black not brown.....brown means that you need to season at a higher heat. I also do mine several times anyway.
When you are done you're ready to cook.
Sometimes acid foods such as chill, spaghetti, or tomato sauces might remove some of the seasoning. So, if your food tastes like metal, your oven needs to be re-seasoned. I just give it a good washing, lightly oil, place it upside down in an oven, and do a mini re-season.
If you have Rust
If a pot gets rusty and the rust is not too bad, even pots that have been used for flower pots can usually be rescued! Scrub the pot and lid with a scouring pad several times and rinse well. Put over a low heat source to dry out all the moisture. While lightly oiling the pot pay particular attention to the inside of the lid and pot. With a white paper towel keep applying a light coat of oil, wipe it out until the towels are coming out oily, but clean. I would then fill the pot with water and about a cup of vinegar and bring it to a rolling boil. Then repeat the white paper towel and oil process over again. When the paper towels come out clean, then re-season as if it痴 a new pot.
If the pot has got paint, or 200 years of burnt on crud, don稚 panic! Just put it in your self-cleaning oven or any oven and bring it to the highest setting, at least 500+ degrees or higher for at least 3 or more hrs. Everything on it will become ash, after letting it cool down in the oven, usually over night. Then use a wire brush on it and then treat it as a normal rusted pot.
CAUTION Remember to always use the proper tools and hot pads to do the seasoning since the pots hold their heat. Never touch a hot Dutch oven without good hot pads. This also works for the tools!!!
