If using the oven to cook the stew, preheat it to 180ºC/350ºF/gas 4. Put a large shallow ovenproof casserole pan on a medium heat with 2 tablespoons of oil. Trim the celery, wash the carrots, peel the onions, then roughly chop it all about the same size as your beef chunks, adding the veg to the pan as you go. Season the veg with sea salt and black pepper, and fry for 10 minutes, or until softened and starting to caramelise, stirring occasionally. Strip in the rosemary leaves, stir in the flour for 2 minutes, then pour in the booze and let it cook away. Pour in the tomatoes, breaking them up with the back of the spoon. Fill the tin with water, swirl around, and pour into the pan. Bring just to the boil, then stir in the meat, season, and cover. Either simmer slowly on the hob or place in the oven for 2 hours, or until the meat falls apart easily. Taste the stew and tweak the seasoning, if needed, then serve with rice or mashed potato, and some lovely veggies, or check out the topping ideas below.