Heat the oil in a large pan over a fairly high heat. Cook the onion and pepper for 3-4 mins until starting to soften and brown slightly. Stir in the curry paste and garlic, then cook for another 1-2 mins. Add the chopped tomatoes and 150ml water. Bring to the boil and bubble for 5 mins.
Turn the heat down, stir in the turkey and potatoes, and cook for another 2-3 mins, then season and add the mango chutney. Scatter with coriander and serve with rice or naan.