Preheat oven to 350 degrees. Separate yolks and whites of eggs. Beat the yolks until they are thick and light colored add flour to the egg yolks. Mix in the flour well into the egg yolks. Add salt and water to the egg whites. Beat egg whites until they have stiff peaks and are dry. Gently fold the beaten egg yolks into the egg whites. Add two tablespoons of butter to an 8 inch oven-proof skillet over medium heat. Spread egg mixture in the skillet and allow to cook for 1 minute before placing the skillet in the oven. Leave in the oven for 10 to 12 minutes or until omelette has set. Serve immediately.