Preheat oven 170°C C.
Heat the oil in an oven tray over medium and brown the pork all sides, then put aside.
Remove excess fat from the tray, then cook the onion and carrots for 5 minutes before stirring in the other ingredients.
Put the pork on top of the vegetables and cover tightly with foil.
Roast in the oven for about 1¾ hours.
Take the joint from the oven and put on a serving dish to rest.
Remove the bay leaf from the vegetables, purée them with a blender then thicken over a medium heat in the tray.
Pour this lovely thick gravy over the sliced pork and your chosen vegetable.