How to Make It
In a small bowl, combine soy sauce, sesame oil, five-spice powder, garlic, crushed red pepper, vegetable oil and cilantro, if desired.
Place chicken in a large ziplock bag. In a separate large ziplock bag, combine onion and bell peppers. Divide marinade between bags, seal and gently toss to coat. Refrigerate both bags for at least 45 minutes.
Preheat broiler, placing a rack about 5 inches from heat source. Line a large, rimmed baking sheet with foil; mist foil with cooking spray. Thread chicken and vegetables onto 4 metal skewers. Place on baking sheet and broil until chicken is cooked through and vegetables are tender, turning often, about 12 minutes total.