Combine the vegetable oil, sesame oil, minced garlic, ginger, dark soy sauce, and honey in a small bowl to create the marinade. Place the chicken pieces in a separate bowl and coat with three-quarters of the marinade, reserving the remainder for basting. Cover the bowl and refrigerate for at least 1 hour or up to overnight. If using wooden skewers, soak them in water to prevent burning. Preheat your BBQ or griddle until searing hot. Thread the marinated chicken onto skewers, alternating with chunks of red pepper and pieces of onion. Continue this sequence until all the ingredients are used, discarding any excess marinade in the bowl. Arrange the skewers on the hot grill and cook for 8–10 minutes, turning three to four times and brushing with the reserved marinade halfway through cooking. Ensure the chicken is fully cooked by slicing into the largest piece to confirm there is no pink remaining. Finish by sprinkling with sesame seeds and torn coriander, and serve immediately with a fresh salad and your choice of rice or potatoes.