Yogurt soup with chillies, coriander and black mustard seeds

Method

1. Mix the yogurt and flour together until smooth, then gradually stir in the vegetable stock.
2. Heat the sunflower oil in a medium saucepan. Add the mustard seeds and cover with a lid. When they begin to pop, uncover and add the ginger, garlic and chillies. Fry for a few seconds, then pour in the yogurt mixture. Bring to a simmer, stirring. Add the coconut milk, curry leaf and some salt to taste and simmer for 3-4 minutes. Stir in the coriander and serve with warm naan bread.