Red Lentil and Spinach Soup

I have a large packet of red lentils just sat in my cupboard so I'm trying to find things to do with them. The first of these recipes is a lentil and spinach soup with a lovely fresh hit of lemon.

Lentil and Spinach Soup (from Kahakai Kitchen)

(Serves 4)

1 tbsp olive oil
2 brown onions, finely chopped
1 tsp ground cumin1 tsp ground coriander200g red lentils
750g vegetable stock
1l water
juice and zest 1/2 lemon
300g baby spinach, roughly choppedsea salt and black pepper

Heat a large saucepan over a medium-high heat. Add the oil, onion, cumin and ground coriander and cook for 6 mins or until the onion is well browned. Add the lentils, stock, water and lemon zest and bring to the boil.
Cover and allow to simmer for 15 mins or until the lentils are soft. Squeeze in the lemon juice and stir through the spinach.. To serve, stir through the salt and pepper , then ladle the soup into mugs or bowls. Serve.