Tenderize the Chicken: If using whole chicken breasts, place them in a resealable bag and pound them to an even thickness. This ensures even cooking., Coating the Chicken: In a bowl, combine flour, cornstarch, salt, and pepper. In another bowl, beat the eggs. In a third bowl, place the Panko breadcrumbs. First, dredge each piece of chicken in the flour mixture, then dip it into the egg, and finally coat it with Panko breadcrumbs, pressing down to adhere., Heat the Oil: In a frying pan, add enough vegetable oil to cover the bottom and heat it over medium heat until hot but not smoking., Making the Bang Bang Sauce: In a bowl, combine mayonnaise, sweet chili sauce, sriracha, and lime juice. Use a whisk to blend the mixture until smooth. Adjust the amount of sriracha for desired spice levels., Frying the Chicken: Once the oil is hot, carefully place the breaded chicken in the pan. Fry for about 5-7 minutes on each side until golden brown and cooked through (internal temperature should reach 165°F or 75°C)., Drain the Chicken: Using tongs, remove the chicken from the pan and place it on a paper towel-lined plate to drain excess oil., Toss the Chicken with Sauce: In a clean bowl, add the fried chicken and drizzle the Bang Bang sauce over it. Toss gently to coat each piece evenly.