1 red chilli, deseeded and chopped, plus extra to garnish (optional)
1 tablespoon medium curry powder
300 ml (1/2 pint) hot vegetable stock
200 g (7 oz) can tomatoes
100 g (3 1/2 oz) baby leaf spinach
25 g (1 oz) chopped coriander leaves, plus extra to garnish
100 ml (3 1/2 fl oz) coconut cream
salt and pepper
4 tablespoons natural yogurt, to serve
Put the lentils into a medium saucepan and cover with 900 ml (1 1/2 pints) cold water. Bring to the boil, skimming off the scum as it rises to the surface, and leave to simmer for 10 minutes until the lentils are tender and just falling apart. Remove from the heat, cover and set aside.
Meanwhile, heat the oil in a large saucepan, add the onion and fry gently for 5 minutes. Add the garlic, ginger and chilli and fry for a further 2 minutes. Stir in the curry powder and 1/2 teaspoon black pepper and cook for a further 2 minutes.
Add the stock, the lentils and their cooking liquid, the tomatoes, spinach and coriander and season with salt to taste. Cover and simmer for 5 minutes then add the coconut cream.
Whizz the mixture with a hand-held blender, until the soup is almost smooth.
Ladle the soup into 4 warmed bowls and garnish each with a spoonful of yogurt, the remaining coriander leaves, freshly ground black pepper and finely chopped red chilli, if desired.