Lemony Moroccan Style Chicken Kebabs

Name: Lemony Moroccan Style Chicken Kebabs
Ingredients: For the marinade; 2 lemons; 6 garlic cloves, peeled; 2 1⁄8 inches slice peeled fresh ginger; 1 teaspoon dried marjoram; 1 teaspoon ground coriander; 1 teaspoon ground cumin; 1⁄2 teaspoon ground turmeric; 1⁄8 teaspoon ground cinnamon; 1 pinch saffron thread (optional); 1 teaspoon light brown sugar; 2 1⁄2 teaspoons kosher salt; 2 teaspoons fresh ground black pepper; 3 tablespoons olive oil; For the kebabs; 2 1⁄2 lbs boneless skinless chicken thighs (trimmed of excess fat and cut into 2-inch chunks also boneless breasts work well too); 1 sweet onion, cut into 1-inch pieces (like Vidalia); 1 red bell pepper, cut into 1-inch squares; 1 yellow bell pepper, cut into 1-inch squares; 2 tablespoons chopped fresh flat-leaf parsley (to garnish); For the Yogurt-Lemon Sauce; 1 seedless cucumber, cut into 1/2-inch dice; 1⁄2 cup chopped fresh cilantro; 2 cups plain yogurt; kosher salt