Prep. time: 10 minutes
Cooking time: 3 hours

1. Melt the butter in a saucepan; add the Caesar's mushrooms, lettuce, salt, pepper and sugar;
2. simmer over low heat, covered, for 30 minutes;
3. add the onions and veal shank; add 2 liters (8 cups) water and 1 liter (4 cups) milk;
4. cover and simmer for 90 minutes; add the rice and cook for 30 minutes longer;
5. remove the shank; blend the soup and correct the seasoning;
6. in a mortar, mash the hazelnuts and 75 g (5 tbsp.) butter to a paste; mix in the egg yolks and cream;
7. pour the mixture into a tureen; gradually blend in the puréed soup, whisking vigorously. Serve hot.