For the chilli and garlic pitta crisps: Mix the pitta wedges in a bowl with the olive oil, garlic and chilli. Place on a baking tray in a single layer and sprinkle with sea salt. Bake for 7-8 minutes or until golden brown.
For the soup: heat the olive oil in a saucepan and add the celery, onion and some salt and pepper. Cook on a low heat with the lid on until soft but not coloured, for about 10 minutes.
Add the cumin and cook for another minute, then pour in the tomatoes and all their juices along with the sugar. Add the chickpeas and the stock and simmer for 5 minutes.
Once the simmering has taken place add the lemon juice and chopped coriander. Check the seasoning and season to taste. Serve in a bowl with the pitta crisps on the side.