Cook the chestnuts, shell them, and puree them. Brown the chopped vegetables with the meat in butter and cook over low heat for 10 minutes. Add 5 cups water, salt, pepper and cook the soup over low heat until vegetables and meat are done. Mix pureed chestnuts into cooked soup and boil for another 5 minutes. Mix heavy cream with eggs yolks, whip into the soup. Adjust salt, serve.