Cast Iron Cleaning Basics
For an individual item, begin by spraying the pan with standard oven cleaner and putting it in a plastic bag. Using a plastic bag will keep the cleaner from evaporating and allows it to work longer.
After a day or two, take it out of the bag and scrub it down with a brass brush. Smith prefers the type made for cleaning whitewall tires, noting it's just the right size "for doing pans." If all the grease doesn't loosen up right away, repeat the process concentrating cleaner on stubborn spots.
Cleaning Multiple Pieces
If you have several dirty items, Smith suggests a soaking solution of one and a half gallons of water to one can of lye mixed in a plastic container. The items should be placed in the solution so that they're covered and allowed to soak for about five days. Remove the pieces and use the same brass brush method to scrub them clean.
Removing mild rust should be done with a fine wire wheel on an electric drill while crusted rust can be dissolved by soaking the piece in a 50 percent solution of white vinegar and water for a few hours. "Don't leave it more than overnight without checking it. This solution will eventually eat the iron!" Smith said on his website.
Once the pan's clean, it should be seasoned. This is done by warming it in the oven for a few minutes then applying a little shortening, vegetable cooking spray, lard or bacon fat. Put the skillet back into a 225 degree oven for 30 minutes. Remove and wipe it almost dry to eliminate any pooled grease. Put it back in the oven for another half hour or so, completing the initial seasoning.The seasoning process will continue with use, especially if you use it to cook fatty foods the first few times it hits the stove.
Cleaning After Use
After cooking, articles stuck to the pan should be loosened with a spoon. Avoid using scouring pads. They cut into the seasoned surface ruining the effect. It's also important to remember not use detergent to clean cast iron, since this will also break down the seasoning. Instead, put hot water in the pan and bring it to a boil. Let the pan soak for several minutes, empty the water and then wipe dry with a paper towel. Reheat the pan and apply just enough grease to cover the surface before stowing it away.
For a step-by-step "how to" guide on cleaning and seasoning cast iron cookware, CLICK HERE.