01 - In a large bowl, combine soy sauce, sesame oil, rice vinegar, garlic, ginger, and black pepper. Add the chicken pieces and toss well to coat. Marinate for at least 15 minutes (up to 2 hours in the refrigerator for extra flavor).
02 - Soak bamboo skewers in water for at least 30 minutes if using, to prevent burning during grilling.
03 - In a small bowl, whisk together mayonnaise, sweet chili sauce, Sriracha, honey, and lime juice until smooth. Set aside until ready to serve.
04 - Thread the marinated chicken pieces evenly onto the skewers, leaving a small space between pieces for even cooking.
05 - Preheat a grill or grill pan over medium-high heat. Grill the skewers for 6-8 minutes per side, or until the chicken is cooked through and nicely charred.
06 - Transfer skewers to a serving platter. Drizzle generously with Bang Bang sauce, then sprinkle with sesame seeds and sliced spring onions. Serve immediately with extra sauce on the side if desired.