Heat olive oil in a large pot over medium heat.
Saute onion until translucent and starts turning golden. Add in garlic and cook for a minute.
Add in carrot and potatoes. Stir well to combine.
To the carrots and potatoes, add the tomato paste, harissa, cinnamon, cumin, paprika, coriander, turmeric and salt.
Add the canned tomatoes and chickpeas and give the stew a nice stir.
Pour in the vegetable stock and bring the stew to a simmer.
Cover and cook for about 30 minutes until the potatoes are fully cooked.
Take the lid off, add the lemon juice and cilantro. Stir and serve warm.