No Cheddar cheese? Use Monterey Jack, Swiss or crumbled blue cheese.
Extra, extras! Cook 2 tablespoons chopped fully cooked ham, 1 tablespoon finely chopped bell pepper and 1 tablespoon finely chopped onion in the butter about 2 minutes, stirring frequently, before adding the beaten eggs.
To warm a plate for serving the omelet, run hot water over the serving plate and dry it thoroughly just before cooking the omelet.
Use a nonstick skillet for easiest omelet cooking.