Step 1: Clean with hot water immediately after use
Cleaning cast iron is a thousand times easier to do if you do it ASAP.
Once you're done cooking, scrape off left behind food bits, and place your cast iron back on the stovetop. Pour a little fresh, hot water into the cast iron.
Step 2: Scrub excess food using a soft dish brush
Excessive scrubbing or abrasion is bad for cast iron, so use a soft bristle brush to gently scrub your cast iron.
Avoid using soap, detergent, abrasive sponges, or steel wool, as these can all strip your cast iron’s coating. Hot water and a soft brush will do just fine!
For a tough job, you can use a small amount of soap or dish detergent, but wash it off immediately after cleaning the stuck-on food or grime.
Step 3: Dry thoroughly with a clean towel
If left wet for too long, cast iron will rust easily. After cleaning, dry your cast iron with a clean kitchen towel.
You can even set it on a burner and turn the heat to low to speed the drying process.
Step 4: Season the pan: Apply a fresh coat of oil
Cast iron loves a good coat of oil, which keeps it healthy and effective for cooking. Pour no more than a tablespoon of neutral oil (see below for more on this) into the pan.
Use a cloth or paper towel to coat the entire pan in a light coat of oil, and let it sit for a while before putting it away.