Melt the lard in a casserole and sear the meat well on all sides. Then take it out of the pot.
Fry the onion and garlic in the frying fat until golden brown, add the chopped tomato, the porcini mushrooms, allspice, bay leaf and thyme and fry everything briefly. Deglaze with water and wine, season with salt and pepper. Bring to a boil.
Put the meat back in the pan and cook covered over a moderate heat for an hour.
At the end of the cooking time, take the meat out of the pot, remove the allspice grains and the bay leaf. Remove the ribs from the meat and cut the roast into slices.
Season the sauce again with salt, pepper and a little chilli and thicken as desired.