Preheat the grill or grill pan to medium-high heat. If using wooden skewers, soak them in water for at least 20 minutes to prevent burning.
In a large bowl, combine olive oil, garlic powder, smoked paprika, salt, pepper, chili powder, and onion powder. Add the chicken pieces and toss well to coat.
Thread the seasoned chicken onto skewers, leaving small gaps between each piece for even cooking.
Place the skewers on the hot grill. Cook for 10–12 minutes, turning occasionally, until the chicken is fully cooked and charred in spots. The internal temperature should reach 165°F (74°C).
Meanwhile, in a small bowl, whisk together mayonnaise, sweet chili sauce, and Sriracha to create the bang bang sauce. Adjust Sriracha to your preferred spice level.
Once cooked, remove skewers from the grill and serve immediately with the bang bang sauce drizzled over or on the side for dipping. Garnish with chopped parsley or cilantro if desired.