I love this recipe and often swap the fish for prawns. The balance of sweet and sour with the pungency of curry and coriander leaves is always popular. Fish is more economical though - choose thick fillets for best results.

Ingredients

• 1 tblsp tamarind pulp
• 1 cup warm water
• 4-6 green chillies, deseeded and diced
• 6 large juicy cloves garlic, crushed and peeled
• 2 tsp ground cumin (or 3 tsp toasted cumin seeds)
• ½ cup oil
• 2 medium-size red onions, peeled and finely diced
• 1½ tsp ground coriander
• 2 tsp garam masala
• 1 tsp each ground turmeric and mild chilli powder
• 4 large juicy tomatoes, blanched, peeled and finely diced
• 1 tsp brown sugar
• 15 dried curry leaves (optional)
• ½ cup lightly packed coriander leaves
• 750 grams lemon fish

Method

1. Stir the tamarind pulp and water together and set aside. Put the chillies into a food processor with the garlic and the cumin or cumin seeds, and process with 2 tblsp of the oil to make a thick paste. Set aside.
2. Heat the remaining oil in a large, heavy-based frying pan and add the onion. Cook, stirring regularly, over a moderate heat for about 12-15 minutes until the onions are golden brown, but not burnt.
3. Stir in the chilli paste, coriander, garam masala, turmeric and chilli powder and cook for a further minute. Add the chopped tomatoes and cook stirring for 5 minutes. Add the strained tamarind water, brown sugar, curry leaves, coriander leaves and 1 tsp salt. Simmer for 2 minutes, then taste to ensure the dish has a good balance of sweet and sour. The sauce should be medium-thick in consistency; if it is too thin, allow it to reduce a little before adding the fish, or if it's too thick, add a little water.
4. Cut the fish into 3cm pieces and add to the curry, turning occasionally until just cooked. This will take about 5 minutes if the sauce is hot. Serve with rice.