Peel onions and garlic. Peel and wash the carrots and celery. Dice everything roughly and boil it up in a pot with approx. 2 l water, 1 teaspoon salt, laurel, peppercorns and cloves. Wash the meat and put it into the pot.
Bring it back to the boil. Cook meat in the boiling broth for about 2 hours, then let it cool down in the broth.
For the sauce, drain the tuna. Rinse anchovy fillets, dab dry. Puree tuna, anchovies, 2 tbsp. capers, mayonnaise, vinegar, wine and lemon peel very finely. Whip cream until semi-stiff and fold in.
Season with pepper, 1 pinch of sugar and salt if necessary.
Wash parsley and shake dry, pluck off leaves and chop. Lift meat out of the stock, dab dry and cut thinly. (Freeze broth in portions.) Serve meat and sauce.
Sprinkle with parsley and remaining capers. Serve with baguette.