Saute the onions in butter until they begin to turn golden. Add the cups of boiling water, salt, pepper, and a dash or cayenne and nutmeg. Add also the bay leaves. Stir well and bring the water to another boil. Reduce the heat to low-med. and cook, covered, for 20 minutes. Add the entire bottle of champagne and bring the soup to yet another boil. Then add the cheese and take care to mix it well in the boiling soup. Beat the egg yolks together with the port wine and add the egg-wine mixture to the soup. Stir well. Turn off the heat and let the soup rest, covered, for 10 minutes. (The soup must not boil again after the egg-wine mixture has been added.). Place 1 slice of fried bread in the centre of each bowl and ladle the soup on top of it. Serve hot. ----