In just a few easy steps, learn how to make the perfect omelet. The key to a fluffy omelet is including a little bit of water or milk with the whisked eggs. Fill your omelet with your favorite ingredients: cheese, spinach, mushrooms or ham all make for a tasty omelet. Make sure to have your toppings ready to go before you drop the egg mixture into a buttered, nonstick pan because cooking an omelet is a fast process!