1
Toast the cumin seeds and chilli flakes in a hot saucepan for about 1 minute, until aromatic.
2
Spoon out about half the mixture and set aside. Heat the olive oil, carrots, split red lentils, hot vegetable stock and milk in the same pan and bring to the boil.
3
Simmer for 15 minutes, until the lentils are plump and soft.
4
Blend the soup with a stick blender or in a food processor until smooth, or leave it chunky.
5
Season to taste and top with plain yogurt and a sprinkle of the reserved toasted spices. Serve with warmed naan bread.