1Preheat oven to 300°F. Pat the beef dry with paper towels and sprinkle with salt and pepper.
2Place a heavy, ovenproof pot over medium-high heat, add a generous drizzle of oil and cook the meat in batches, without crowding the pan, browning it well on all sides. Remove from the pot and add the onion and celery, if using. Cook for 3-4 minutes, until soft and starting to loosen the browned bits in the bottom of the pan. Add the garlic and tomato paste and cook for another minute. Add the vinegar and cook for another minute.
3Add the stock and red wine, cover and cook for 2 1/2 hours, until the meat is very tender. Add the potatoes, carrots and parsnips, stir to coat everything well and return to the oven for 30-40 minutes, until the vegetables are tender. (If you're adding peas, stir them in for the last 5 minutes.) Serve hot.