Cook the veal and beef in the water until tender. Remove the meats from stock and reserve for use as slices with Horseradish Sauce.
Brown the potatoes, onions and leeks in the butter over low heat for 10 minutes.
Add all the ingredients except the cream to the liquid in which the meat was cooked, and cook 1½ hours. Press through a sieve.
Reheat, and add the cream slowly. If the soup is thicker than you want it to be, add a little more cream.
Serve with croutons.