Preheat the oven to 160 degrees C. Heat the oil in a large flameproof casserole dish. Add the beef and brown it over a medium– high heat for 6–8 minutes or until it is well coloured on all sides. Set the meat aside on a large plate.
Reduce the heat to medium. Add the onions, celery and garlic and cook, stirring frequently, for 3 minutes or until the onions begin to soften. Add the wine and let it bubble for about 1 minute, then add the tomatoes and grated carrot. Cook for a further 2 minutes.
Return the beef to the casserole dish together with any juices that have collected on the plate and the chopped thyme. Tuck a piece of baking paper or foil around the top of the meat, turning back the corners so that it doesn't touch the liquid, then cover with a tight-fitting lid. Transfer the casserole dish to the oven and cook for 2 1/2 hours.
About 20 minutes before the end of the cooking time, bring the stock to the boil in a deep saucepan with a lid. Add the potatoes, celeriac, swede and sliced carrots. Cover and simmer gently for 12–15 minutes or until they start to become tender.
Remove the beef from the casserole and set aside. Remove any fat from the cooking liquid, either by spooning it off or by using a bulb baster, then purée the casseroled vegetables and liquid in a blender or food processor until smooth. Season to taste.
Drain the potatoes and other root vegetables, reserving the liquid. Make a layer of the vegetables in the casserole dish, put the beef on top and add the remaining root vegetables and their cooking liquid. Pour over the puréed sauce. Cover the casserole and return to the oven to cook for 20 minutes or until the root vegetables are tender.
Remove the beef to a carving board, cover and leave to rest for 10 minutes. Keep the vegetables and sauce in the oven turned down to low.
Carve the beef and arrange on warmed plates with the vegetables and some of the sauce. Sprinkle with the parsley and serve immediately.
Swede is a member of the cruciferous family of vegetables. It is a useful source of vitamin C and betacarotene and rich in phytochemicals that are believed to help protect against cancer.