Generously season the pork with salt.
In a heavy saucepan with a lid, heat the olive oil and brown the meat on all sides. Remove the meat and put to one side. Lower the heat and pour the vinegar into the pan. Bring to the boil, and reduce the liquid by half. Add the wine, 100 ml (4 fl oz) water, the peppercorns and bay leaves and lower the heat to a simmer.
Return the pork to th