Put the onion and garlic in a processor and chop until almost mushy. In a wok or deep sauté pan, heat the oil and fry the onion mixture until it starts to brown, then stir in the balti paste, tomato puree and cumin and fry for a further minute.
Stir in the peanut butter and fry on a low heat until the oil begins to separate and the sauce has darkened.
Add the tomatoes, coconut milk, lime juice, 2 teaspoons of coriander, sultanas and stock and gently simmer for about twenty minutes. Add the cooked turkey and simmer for five minutes or until hot and heated through.
Serve with rice, thick yoghurt and sprinkle with the remaining teaspoon of coriander.