Prepare the Chicken: In a large bowl, mix the chicken pieces with cumin, ginger, turmeric, cinnamon, saffron, salt, and pepper. Let it marinate for at least 30 minutes, or longer if you have the time. This allows the spices to infuse the chicken with their aromatic flavors.
Cook the Onion and Garlic: In a tagine or large Dutch oven, heat olive oil over medium heat. Add the chopped onion and garlic, and cook until softened, about 5 minutes. Stir in the marinated chicken pieces, browning them on all sides, about 5-7 minutes.
Simmer: Once the chicken is browned, add the chicken broth, preserved lemon slices, and olives to the pot. Bring to a simmer. If you’re using a tagine, cover it with the cone-shaped lid. If you’re using a Dutch oven or regular pot, simply cover it with a lid. Let it cook over low heat for about 45 minutes, or until the chicken is tender and the flavors have melded together. The sauce should reduce and thicken slightly.
Garnish and Serve: Once the chicken is cooked through, sprinkle fresh cilantro over the top before serving. Serve with couscous or warm crusty bread to soak up the delicious sauce.