Chicken and Lentil Soup

1tsp cumin and coriander seeds
1tbsp oil
1 small onion(finely chopped)
2 garlic cloves(finely chopped)
14 curry leaves
1.3 litres chicken stock
100g green lentiles
100g red lentils
227g can chopped tomatoes
100g cooked chicken breast (cut into small cubes)
150 carton natural yoghurt
fresh coriander

1.dry fry the cumin and coriander seeds in a small pan for 1-2 mins until fragrant, then using a pestle.
2.heat the oil in a large pan, andd the onion and fry for 3-4mins. stir in the garlic and curry leaves, fry for a minute or until fragrant, then stir in the ground cumin and coriander and the tumeric. Pour in the stock and bring to boil. Add the green lentils, lower the heat and simmer, uncovered for 10 mins . Stir in the red lentils and simmer for 15 mins or until thickened.
3.Add the tomatoes and chicken and heat through. Stir in one tbs of youghurt and half the coriander. Mix the rest of the yoghurt and coriander toghther and serve separately. for swirling on top of the soup