1. Heat the oil in a large frying pan and fry the turkey in batches until lightly browned. Remove and reserve.
2. Add the onion to the pan and fry until softened. Stir in the coriander, cumin, turmeric, chilli, ginger and garlic, and fry gently for 2 minutes.
3. Add the tomatoes, courgettes and water and return the turkey to the pan. Cover and simmer gently for 15 minutes.
4. Stir the cornflour into the soured cream until evenly mixed and bring back to simmering point. Stir in the coconut and seasoning. Heat gently until the coconut melts.
5. Serve sprinkled with freshly chopped coriander, accompanied by rice, naan bread and chutney.