Over easy is easy on cast iron. I tend to put a spoon of butter, spread it a little, and crack the egg into it. The butter should sizzle but not brown too quick

Over easy is easy on cast iron. I tend to put a spoon of butter, spread it a little, and crack the egg into it. The butter should sizzle but not brown too quickly. You should be able to slide the egg in the pan like on a nonstick.