01 - In a mixing bowl, whisk together the pineapple juice, soy sauce, brown sugar, ketchup, rice vinegar, minced garlic, grated ginger, vegetable oil, and black pepper until well combined.
02 - Add the chicken cubes to the marinade, tossing to ensure each piece is thoroughly coated. Cover the bowl and refrigerate for at least 2 hours, preferably overnight for maximum flavor penetration. Reserve 2 to 3 tablespoons of the marinade before adding the raw chicken for basting during grilling.
03 - If using wooden skewers, submerge them in water for at least 30 minutes to prevent burning on the grill.
04 - Preheat an outdoor grill or grill pan to medium-high heat, approximately 400°F.
05 - Thread the marinated chicken, red bell pepper, yellow bell pepper, red onion, and pineapple cubes onto the skewers in an alternating pattern, distributing the ingredients evenly across each skewer.
06 - Place the kebabs on the preheated grill and cook for 12 to 15 minutes, rotating every 4 minutes for even charring. Baste occasionally with the reserved marinade. The chicken is done when it reaches an internal temperature of 165°F and has a lightly charred exterior.
07 - Remove the kebabs from the grill and let them rest for 2 minutes. Serve hot alongside steamed rice, coconut rice, or a fresh green salad.