You can use a touch of regular dish soap to help dislodge sticky food, but don’t use too much. Never use bleach or any kind of harsh cleanser. Never put your cast iron skillet in the dishwasher. [2] X Research source The detergent will corrode the iron.
You can also burn off caked food. Turn up the oven to 500 °F (260 °C) and put the skillet inside for an hour or so. The food will turn to ash, and you’ll be able to brush it off and rinse the skillet. However, if you use this method you’ll need to re-season the skillet, since that will get burned off as well.
After this first washing, you won’t be using a scrub brush on the skillet again, since it will take off the precious seasoning you’ll be working to preserve. Make sure to dry the skillet well, so that it doesn’t create steam when you put it in the oven.
Try not to miss any spots when you’re covering the skillet with fat. If you miss a spot, it won’t get a coating of seasoning, and will be more prone to rusting.
When you remove the skillet, check for rust. If you still see rust spots, use a scrub brush to scrub them away. Don’t soak the skillet for more than 4 hours, or the iron will start to degrade. You just want to soak it long enough to take off the rust. [13] X Research source
