I have a cast iron pizza pan- one of those lodge logics preseasoned ones- that I use daily. It had a really nice black finish, but then my dumb sister poured concentrated dishwashing detergent on it, and now there is a lighter-colored rivulet going through the black. The bad news: there seems to be an awful lot of black stuff flaking off the border and sticking to the food. What do I do?? Clean all black off and start from scratch? Does anybody know?

Or does cast iron stick little black flakes to your food and that's just that?