Sauté the onions and bell peppers first until the onions turn light yellow.

Add the potatoes, zucchini, and spices, and stir. Then add the chicken and tomatoes. If you like, add 1 teaspoon of tomato paste. Stir everything together, cover, and cook over low heat for 20 minutes.

Meanwhile, parboil the rice until it's halfway cooked, then drain. Layer the rice over the chicken mixture, cover, and cook on very low heat for 20 to 30 minutes. Serve hot.