5ml (1 tsp) turmeric
2.5ml (½ tsp) salt
10ml (2 tsp) plain flour
15ml (1 tbsp) lemon juice
4 x 175g (6oz) cod or haddock steaks
1 onion, halved lengthways
5ml (1 tsp) cumin seeds
10ml (2 tsp) coriander seeds
5ml (1 tsp) black peppercorns
2 cloves garlic, peeled
5cm (2 inch) piece fresh root ginger, chopped
1 small hot red chilli, seeded
45ml (3 tbsp) vegetable oil
3 mild green chillies, seeded and cut into thin strips
4 tomatoes, peeled, seeded and chopped
10ml (2 tsp) tomato purée
400ml (14fl oz) can coconut milk
coriander sprigs, to garnish
basmati rice, to serve