You can clean your cast iron with mild soap and by using a scraper. While soap has been said to ruin cast iron, this is usually untrue with modern cleaning products. Dish soaps generally don’t contain the harsh chemicals that you need to worry about anymore. There are also many kinds of scrapers you can use on cast iron. It isn’t as easy to scratch as other cookware.If you don’t want to use a plastic or nylon scrubber, you can also use a sponge and salt.