01 - Whisk together buttermilk, hot sauce, garlic powder, onion powder, salt, and pepper in a large bowl. Submerge chicken thighs completely. Cover and refrigerate for 2 hours minimum, preferably overnight for maximum flavor penetration.
02 - Combine flour, cornstarch, paprika, baking powder, cayenne, salt, and black pepper in a shallow dish. Mix thoroughly to distribute spices evenly.
03 - Pour vegetable oil into deep fryer or heavy-bottomed pot. Heat to 350°F, maintaining temperature throughout cooking for optimal crispiness.
04 - Lift chicken from marinade, allowing excess liquid to drip off. Press each piece firmly into flour mixture, turning to coat all sides. Create thick, craggy coating for maximum crunch.
05 - Lower chicken carefully into hot oil. Fry 6–8 minutes per piece, turning once halfway through. Cook until deep golden brown and internal temperature reaches 165°F. Transfer to wire rack to drain.
06 - Lightly toast cut sides of burger buns until golden and warm to the touch.
07 - Combine mayonnaise with hot sauce in small bowl. Adjust ratio to taste preference for spicy kick.
08 - Spread spicy mayo on bottom bun. Layer lettuce leaf, fried chicken fillet, tomato slice, and pickle chips. Cap with top bun and serve immediately while chicken remains crispy.