Mix paprika, pepper, cinnamon, cumin, ginger and salt. Mix 1 tablespoon of the spice mixture with flour in shallow dish. Coat chicken with flour mixture. Reserve remaining spice mixture. Heat oil in 4- to 6-quart Dutch oven on medium-high heat. Add chicken; cook 7 minutes or until chicken is browned on both sides. Remove chicken from pan. Set aside.Stir onions, carrots, garlic and remaining spice mixture into pan. Cook and stir 5 minutes or until onions are lightly browned. Return chicken to pan. Add potatoes, olives, preserved lemon, 2 tablespoons each of the cilantro and parsley, bay leaves and stock. Bring to boil. Reduce heat to low; cover and simmer 1 hour or until chicken and potatoes are tender. Sprinkle with remaining 2 tablespoons each cilantro and parsley. Serve with cooked couscous, if desired.