Heat the oil in a large pot over a medium heat and sauté the onion, celery and garlic until translucent.
Add the lamb, turmeric, cinnamon, ginger, paprika, cumin and ground coriander to the pot and stir to toast the spices and brown the meat.
When the meat has browned, pour in the vegetable stock, carrots, chickpeas, lentils, tomato purée, and chopped tomatoes and stir well. Bring to the boil then reduce heat to low and simmer for 20-30 minutes
Add the vermicelli and let cook for 5 minutes
Add the chopped coriander and parsley (reserving some for the garnish) and the spinach. Once the spinach has wilted, your soup is done. Add salt and pepper to taste
Ladle into bowls and serve with harissa paste and a lemon wedge