Peel and finely chop the onion. Peel the carrot. Dice it. Trim and finely slice the celery.
Warm 1 tbsp olive oil in a large pan. Add the onion, carrot and celery. Season with salt and pepper. Cook gently for 5 mins till the veg start to soften. Stir often. Keep the heat low. If the veg look like they might stick, add a splash of water.
While the veg cook, peel and crush or chop the garlic. Add it to the veg with 2 tsp of the ras el hanut. Stir and fry for 1 min.
Drain and rinse the chickpeas. Stir them into the pan with the chopped tomatoes. Fill the tomato can with warm water (around 400 ml) and add that to the pan too. Pop a lid on the pan.
Turn up the heat. Bring the stew to the boil then turn the heat down to low. Simmer for 20 mins, stirring every now and then. If the stew looks like it’s getting too thick, turn the heat down (if possible) and add another splash of water.
Warm a small, dry frying pan over a low heat. Measure out ½ tsp cumin seeds. Toast them in the pan for 1-2 mins till they smell nutty and start to pop. Shake every now and then so they don’t catch. Take off the heat.
Finely chop the parsley. Stir half into the stew. Taste and season with salt and pepper if you think it needs it.
Ladle the stew into warm bowls. Top each bowl with 1 tbsp of the yogurt, then sprinkle with the toasted cumin seeds and the remaining parsley. Serve straight away.