Cast iron griddles are popular at the campfire and in the kitchen of many cooks. They conduct heat well, are non-stick when properly seasoned and are a versatile cooking tool. Cleaning a cast iron griddle is different from cleaning a griddle that isn't cast iron. Clean it improperly, and you risk ruining your cast iron griddle. Proper cleaning techniques will make your cast iron griddle usable for years.
Let the cast iron griddle cool to room temperature before cleaning it to prevent burns and possible damage to your griddle.
Rinse the cast iron griddle with clean water. Soap can ruin a seasoned griddle, so don't use it. Wipe it with a clean sponge or rag.
If there's food stuck on the griddle, combine 2 tbsp. each of water and kosher salt to make a thick salt paste. Scrub the stuck food off the griddle using the paste, and rinse with water.
Dry the griddle and rub the cooking surface all over with a little bit of cooking oil on a towel. Any cooking oil will do, but you may want to use peanut oil if you use your griddle over an open fire or otherwise cook with it at very high temperatures. Peanut oil will cause less smoke at high heat than other oils. There should be just a light coating of oil on your griddle. Wipe with a dry towel to remove any excess oil.
If your griddle isn't yet fully seasoned, you can put it in the oven at 250 degrees F for an hour to additionally season it before storage. Let it cool in the oven, wipe it down with a towel one more time and store it.