Bengali yogurt fish

Method

1. Heat the oil in a saucepan. Add the onion and cook until soft and lightly golden. Add the ginger and garlic pastes and cook over a gentle flame for around two minutes, stirring often; the garlic should smell cooked. Stir in the spices, salt and green chillies. Pour in the pureed tomatoes and 150ml water and cook over a moderate flame until the liquid has evaporated, then continue stirring until the tomato takes on the rich colour of tomato puree. Stir in the yogurt until really well blended.
2. Pour in 200ml water, bring to a gentle boil, stirring constantly, then simmer for five to eight minutes, or until the sauce has the consistency of single cream. Taste; you may want more salt or chilli powder.
3. Add your fish and shake the pan to coat the fillets with the sauce. Cover and cook gently for three to five minutes, or until the fish is cooked through. Serve sprinkled with a little fresh coriander.