Proper care and cleaning are required to keep cast-iron frying pans in top shape. Well-seasoned cast iron cookware provides a virtually nonstick cooking surface,and the pans will last several lifetimes. The pans require a bit of special handling and some added effort to perform their best.
Cast-iron frying pans should be cleaned as soon as possible after use, ideally while the pan is still warm. Soap is not necessary; instead, use just hot water and a scrubber or stiff brush inside and out. If food is stuck on, rub it with a paste of kosher salt and water until it's dislodged. Rinse the skillet thoroughly, and wipe it dry with a towel; then heat the pan on the stove over low heat to complete the drying. Apply a light coat of food-safe oil with a paper towel, and wipe it with a fresh paper towel to remove the excess.
The Soap Debate
Some sources say to never use soap on a cast iron frying pan. Others say using a mild soap is just fine. The seasoning on cast iron cookware is made up of polymerized oils. Mild soap alone won't damage the polymerized oil layer, but it can remove any residual oils sitting on top, reducing the nonstick qualities of the cast iron. Soap can cut odors that are caused by rancid oils, or freshen a smelly skillet. Use mild soap and don't scrub too hard, rinse and dry well, then treat your skillet to a good heating and oiling.
Dealing With Rust and Odors
If you have a skillet that has rusted, is old and gunky, or has an unpleasant odor, start by scrubbing with soap and water to see if that solves the problem. If not, cut a potato in half and use the cut edge of the potato to scrub the skillet with coarse salt. Continue adding salt and scrubbing until all the rust is removed. An alternate method is to use medium-grit steel wool to scour the entire skillet inside and out to remove all traces of rust and old seasoning layers. Wash and reseason your skillet before using.
Oils and Seasoning
Seasoning a cast iron frying pan requires oil and heat. Any food-safe oil will work, lard, bacon fat, corn oil, vegetable oil and shortening are all recommended. Food-grade flax seed oil may offer the hardest, most durable finish. To season a cast iron frying pan, lightly coat a clean, dry pan with the oil of your choice. Place the pan in your oven on a cookie sheet or aluminum foil to catch any possible drips. Turn the oven up to 450- to 500-degrees Fahrenheit and bake for one hour. Turn the oven off, let the pan cool down enough to handle, then repeat the process until you get the level of smooth coating you want.