Fry six large onions cut into slices with a quarter of a pound of butter till they are of a bright brown, then well mix in a tablespoonful of flour, and pour on them rather more than a quart of water. Stew gently until the onions are quite tender, season with a spoonful of salt and a little sugar; stir in quickly a liaison made with the yolks of two eggs mixed with a gill of milk or cream (do not let it boil afterwards), put some toast in a tureen, and serve very hot.