Separate the eggs. Add half an eggshell of water for each egg, to the yolks: beat them with a wooden spoon until creamy; Whisk the whites until they stay in the basin when turned upside down. Gently fold the whites into the yolks. Have the butter ready in the pan as for the French Omelette. Pour in the egg mixture, and cook until it is golden brown on the underside. Then put the pan under the grill and lightly brown the top. Fillings are usually spread over the cooked omelet. Now run a palette knife round the edge of the pan. Fold the omelet over and slip on to a hot dish.