1. Heat oven to 150C. Toss the beef in seasoned flour. Heat the oil in a large flameproof casserole. Fry the beef over a high heat until browned all over — it's easiest to do this in batches. Remove with a slotted spoon and set aside.
2. Add 2 tbsp water and the onion to the pan, stir well over a medium heat, scraping up the crusty bits from the bottom of the pan. Lower the heat and fry gently for 10 min, stirring occasionally until the onions have softened.
3. Tip in the carrots, parsnips and bay leaf, and then fry for 2 min more. Return the beef to the pan, stir in the tomato paste, wine if using, and stock, then bring to the boil. Cover and cook in the oven for 1¾-2 hrs until the meat is tender. Can be made up to 2 days ahead or frozen for up to 1 month. Defrost thoroughly in the fridge before topping and baking. Take out of the oven and increase the temperature to 190C.
4. To make the topping, sieve the flour and baking powder into a bowl and add half the cheese. Mix olive oil and milk, then stir into the flour to make a soft, slightly sticky dough. Add more milk, if necessary. Spoon the dough over the meat and vegetables, sprinkle with the remaining cheese and bake for about 15 min until golden, risen and cooked through.