Heat the remaining oil and cook the onion, garlic and ginger with some seasoning for 8 mins until soft. Add the curry powder, potato and carrots, and cook for a few mins more. Stir in the tomato purée, 500ml water or vegetable stock, and the beef. Cook on a medium heat for 20 mins or until the potatoes are tender. Serve with basmati rice, fresh coriander, and mango or lime chutney.