Heat 1 tbsp oil on heavy bottomed sauce pan, and add the chicken cubes, red onion, garlic, ginger, curry powder, chilli powder and turmeric, cook for 10 minutes over a medium heat.
(if using cooked chicken do not add at this point)
Add tomatoes and water/stock and simmer for 20 minutes.
Stir in the cooked chicken (where appropriate) coconut milk, mango chutney and coriander. Bring to the boil and simmer for 5 minutes.
Serve with rice and Naan bread.