A number of you have asked (and please keep the questions coming!) about the care and feeding of cast iron... So...
I LOVE my cast iron pans. No, they aren't for everything... a delicate white sauce? Bad Idea. BUT... if you are lucky enough to have inherited your mother's or grandmother's cast iron, and it's well seasoned... you're a lucky cook.
After years of cooking and seasoning, they become virtually non-stick. And they hold heat like nobody's business. If you DIDN'T inherit... then go to a yard sale, or a junk shop... buy a crappy, rusty old pan, and start seasoning. Or buy some brand new... they're cheaper than cheap flimsy aluminum... and will last forever.
My seasoning method is simple: scrub it hard (especially if you bought an old rusty pan!)... steel wool and soap (the last time those 2 things will ever touch it!!), dry it well, fill it with vegetable oil, and put it in a 350o oven for about an hour. Let the oil cool, pour it out, dry the pan with paper towels... et voilà.
Now, every time you use it, rinse it with hot water and, if needed, use a plastic scrubby... no soap, no steel wool. A stubborn mess may require soaking for a bit... or even some oil and coarse salt to scrub... but forget the soap and steel wool or you'll be back to square one. Dry it on the stovetop, film it with a little vegetable oil, and put it away.
It will darken over time, and begin to acquire a mirror-like finish. Just remember how to clean it. I have some of my mother's, and all of my mother-in-law's, as well as the ones I bought in the Green Room of the Alliance Theatre in Atlanta when I was a young actor doing Othello with Paul Winfield and Richard Dreyfuss... 30+ years ago!! And the chicken I roasted in one of those skillets a while ago... I didn't even have to scrub!
And just in case a well-meaning friend soaps and scrubs a beloved skillet... all is not lost. Just start from the beginning and season all over again.