To make the bang bang sauce: Whisk mayonnaise, sweet chili sauce, and Sriracha in a bowl until evenly combined. Set aside.
Place cubed chicken, oil, garlic powder, paprika, salt, and pepper in a separate bowl. Stir until evenly coated.
Preheat an outdoor grill for medium-high heat. Lightly oil the grate.
Thread chicken onto skewers; baste on all sides with bang bang sauce. Place skewers directly on the grate. Grill for 4 minutes. Turn skewers over, baste, and grill 4 minutes more.
Turn skewers over one last time, baste with remaining sauce, and grill until chicken is no longer pink at the center and juices run clear, about 2 minutes. An instant read thermometer inserted near the center should read 165 degrees F (74 degrees C). Remove from the grill and serve immediately.
