Onion Soup (TAC) unusual

One quart of milk, six large onions, yolks of four eggs, three tablespoonfuls of butter, a large one of flour, one cupful of cream, salt and pepper.  Put the butter in a frying pan. Cut the onions into thin slices and drop into the butter.  Stir until they begin to cook; then cover tight and set back where they will simmer but not burn, for half and hour. Now put the milk on to boil, and then add the dry flour to the onions and stir constantly for three minutes over the fire, then turn the mixture into the milk and cook fifteen minutes.  Rub the soup through a strainer; return to the fire, season with salt and pepper.  Beat the yolks of the eggs well, add the cream to them and stir in the soup. Cook three minutes, stirring constantly. If you have no cream, use milk, in which case add a tablespoon of butter at the same time. Pour over fried croutons in a soup tureen. This is a refreshing dish when one is fatigued.