Heat the oil in a flameproof casserole dish over a medium-high heat. Fry the onions and celery for a few mins until turning brown. Add the beef and brown all over for 3-4 mins. Pour in the wine, if using, and let it reduce by half. Add the stock and toss in the swede, potatoes, thyme and bay leaf. Season and bring to the boil.
Reduce the heat, cover with a lid and leave for 1 hr. If you want to reduce the liquid a little, remove the lid, turn up the heat and cook for a further 10-15 mins or until the sauce has thickened.
Season to taste and remove the thyme sprigs and bay leaf. Serve with some green veg, if you like.
