Marinate the chicken by whisking buttermilk, garlic powder, onion powder, paprika, salt, and black pepper in a bowl. Add chicken and refrigerate for at least 1 hour.
Make the Bang Bang Sauce by whisking together mayonnaise, sweet chili sauce, sriracha, honey, lime juice, and garlic powder. Adjust to taste.
Dredge the marinated chicken in a mixture of flour and panko. Fry in hot oil until golden brown, about 3 to 4 minutes per side. Drain on paper towels.
Assemble sliders by toasting the buns, spreading Bang Bang sauce, adding fried chicken, lettuce, onion, and pickles. Garnish with cilantro and top with the bun.
Serve with extra Bang Bang sauce for dipping.
Notes
For a lighter option, bake chicken instead of frying. Adjust spice level by varying the sriracha amount.