Cover the well-watered calf’s head with water and boil it with root vegetables, peppercorns, bay leaf and sea salt for about 2 hours until soft. Let it cool down and keep about 100 ml of the stock. Remove the meat and the tongue. Cut everything into small cubes and boil down well with Madeira and veal jus. Chop the cooked root vegetables and parsley, add to the mixture and season to taste. Fill the ravioli as described in the basic recipe and place on a floured baking tray. Then boil the calf’s head stock put aside, stir in cold butter and thicken the stock with it. In another pan, sauté the washed spinach leaves with a little butter and season with salt and pepper. Meanwhile, add the cooked, drained ravioli to the sauce and toss briefly. Squeeze the spinach, arrange on warmed plates, place the ravioli on top and pour the sauce over it. If desired, sprinkle with white truffles.