Mix together the olive oil, harissa paste, zaatar, salt, and pepper.
Top and tail the carrots and place them on a baking sheet.
Peel and cut the onion into wedges and add to the carrots.
Remove the garlic cloves from the head of garlic (do not peel) and place them on the baking sheet, then add the celery.
Coat the vegetables with the harissa and olive oil mix, then roast in the oven at 200°C or 400°F for an hour.
Remove the vegetables from the oven and place them in a blender along with the vegetable stock, and blend. Pass through a fine mesh sieve and return to a 20cm or 8" saucepan to keep warm.Passing the soup is optional!
Dry the chickpeas as thoroughly as you can.
Heat 5-7mm (¼") of neutral oil in a 24cm or 10" frying pan and heat it to around 160°C or 320°F, then add the chickpeas and a lid; no matter how well you dry the chickpeas, they will spit.Give them a shake every 30 seconds and cook for 2-3 minutes,
Drain the chickpeas on kitchen paper and give them a coating of sumac, and serve them on top of the soup.