Preheat oven to 350 degrees F.
Coat the chicken in the Ras el Hanout spice.
Heat the olive oil in a dutch oven or other oven-safe pot over medium-high heat. When the oil is hot, add half the chicken skin side down and brown for 3 minutes, then flip and brown for another 2 minutes. Remove chicken and set aside. Repeat with the remaining chicken and remove it from the pot.
Add the onions to the pot with the leftover chicken juices and cook for 5 minutes or until translucent and slightly browned, stirring occasionally.
Add the garlic and stir for 30 seconds. Then add the saffron and tomato paste and stir till combined.
Add the chicken stock and cherry tomatoes. Then nestle the chicken thighs in the pot, covering with as much of the juice, tomatoes, and onions as possible.
Cover the pot and put in the oven to cook for 20 minutes. Add the preserved lemon and green olives to the pot and cook, covered, for another 20 minutes.
Serve the chicken with a side of rice or couscous and topped with optional cilantro or parsley.