Sauce: In a large pan, heat the olive oil and sauté the onion for 5 minutes until translucent. Add the garlic and cook for 1 more minute.
Build flavor: Add the tomato paste and cook for 2 minutes to caramelize. Stir in the tomatoes, harissa or roasted pepper paste, spices, and mix well.
Cooking: Add the chickpeas with their liquid and the stock. Simmer for 15-20 minutes until the sauce thickens. Adjust seasoning with salt and pepper.
Yogurt: In a bowl, mix all the ingredients until creamy and aromatic.
Serving: Spoon the chickpeas into a deep plate, top with dollops of yogurt, and drizzle with olive oil or extra harissa (in the spicy version).