Marinate the Chicken:
In a large mixing bowl, combine the chicken pieces and buttermilk. Cover and let marinate for at least 30 minutes in the refrigerator (or up to 4 hours for extra tenderness).
Prepare the Breading:
In another bowl, whisk together the flour, cornstarch, paprika, garlic powder, salt, and pepper.
Coat the Chicken:
Remove the chicken from the buttermilk, shaking off any excess. Dredge the chicken pieces in the flour mixture, pressing gently to ensure they are fully coated.
Fry the Chicken:
Heat about 2 inches of vegetable oil in a deep frying pan or pot to 350°F (175°C). Fry the chicken in batches, turning occasionally, until golden brown and crispy (about 4–5 minutes). Remove and drain on paper towels.
Make the Bang Bang Sauce:
In a medium bowl, whisk together the mayonnaise, sweet chili sauce, sriracha, and honey until smooth and creamy.
Toss and Serve:
Place the fried chicken in a large bowl and drizzle the Bang Bang Sauce over the top. Toss gently to coat the chicken evenly.
Garnish and Enjoy:
Transfer to a serving platter, garnishing with chopped green onions and sesame seeds. Serve immediately as an appetizer, snack, or over rice.