• 1 kg (2 lb 4 oz) boneless, skinless chicken thigh fillets, cut into bite-sized pieces
• 3 onions, thinly sliced
• 35 g (1¼ oz/½ cup) shredded dried coconut
• 2 tablespoons tamarind purée
• 2 teaspoons finely grated fresh ginger
• 1 lemongrass stem, trimmed, bruised and cut into 4 cm (1½ inch) lengths
• 1 garlic clove, crushed
• 1 teaspoon ground turmeric
• 1 teaspoon red chilli powder
• 60 ml (2 fl oz/¼ cup) vegetable oil
• 30 g (1 oz/1 cup) coriander (cilantro) leaves
• 10 g (¼ oz/½ cup) mint leaves
• 4 green chillies, roughly chopped
• 2 tablespoons lemon juice
• 250 g (9 oz) plain yoghurt

Put the chicken in a wide heavy-based saucepan with the onion, coconut, tamarind, ginger, lemongrass, garlic, turmeric, chilli powder, oil and 500 ml (17 fl oz/2 cups) water. Bring to the boil, then reduce the heat to low. Cover and leave to simmer gently for 35 minutes, then remove the lid and increase the heat to high so the sauce boils down a little and starts to thicken.

Meanwhile, put the coriander, mint, chillies and lemon juice in a food processor or blender. Add 2 tablespoons water and process to form a smooth paste.

When the curry has reduced and the meat is thickly coated in the sauce, pour the fresh herb paste into the curry, stir to combine, then cook for a further 4 minutes.

Divide among four bowls and top with a spoonful of yoghurt. Serve with steamed rice and naan bread or soft flatbread.