This flavor-packed sheet pan supper is a very distant cousin to classic shawarma. It has all the requisite flavors and is finished with a flavorful tangy tahini yogurt sauce. Serve it as a main dish or as a side along with roast chicken, fish, or lamb.
In a large bowl, whisk together the olive oil, lemon juice, cumin, coriander, paprika, turmeric, cayenne, garlic, and salt until blended. Add the cauliflower, chickpeas, and onion and stir everything together very thoroughly so that the marinade evenly coats the cauliflower.
Transfer to the baking sheet and spread it out. Roast until the onions are tender, and the cauliflower begins to brown (and even blacken) on the edges, about 30 minutes.