Preheat your oven to 425°F (220°C).
Roast the veggies: In a deep 8x12-inch (or similar size) baking dish, toss together the cherry tomatoes, garlic, chopped shallots/onion, cilantro stems, thyme, cinnamon, olive oil, ½ teaspoon salt, and ¼ teaspoon black pepper. Roast uncovered for 15 minutes.
Add chickpeas: Remove from oven, stir in chickpeas (if using), and roast for another 10–15 minutes, until the tomatoes burst and everything is tender and lightly caramelized.
Add rice and water: Sprinkle the rinsed rice evenly over the roasted mixture, do not stir. Pour 2 ½ cups boiling water over the rice. Season with the remaining ½ teaspoon salt and ¼ teaspoon pepper. Cover tightly with foil.
Bake again: Return to the oven and bake for 25 minutes. Remove and let rest, still covered, for 10 minutes.
Finish and serve: Uncover and gently fluff the rice. Stir in the chopped cilantro leaves. Taste and adjust seasoning if needed. Serve hot.
