Place the onion, potato, carrots, courgettes in the bowl of a food processor and process till chopped. Do not puree the vegetables, they should be chopped as if they were hand grated.
Pour the oil in a large pot, and then add the vegetables and the passata. Sprinkle with paprika, pepper, cinnamon, cumin and turmeric, mix well, then add the coriander, mint and parsley. Place the celery on top, cover with water and simmer for 1 hour.
Add the tomato puree, chickpeas and freaked. Add water if necessary and cook a few more minutes until the freekeh is tender.
Remove the celery (it can be reused in another vegetables soup). Season to taste and serve hot.