Add a splash of veg oil to a large pot on medium-high heat. Season the ribs with salt and pepper and sear them a few at a time in the pot, until they're evenly browned on all sides. Put all the ribs in the pot, along with the bay, thyme, garlic, onion and peppercorns. Add enough cold water so the meat's submerged about 2 cm below the surface. Turn the heat down to medium-low and let simmer for 2 hours. Remove the meat and set aside.