01 - In a large bowl, whisk together buttermilk, salt, garlic powder, onion powder, cayenne pepper, and black pepper until fully combined. Add chicken pieces and turn to coat completely. Cover bowl and refrigerate for at least 2 hours, preferably overnight for maximum flavor penetration.
02 - In a separate large bowl, combine all-purpose flour, paprika, salt, black pepper, cayenne pepper, and baking powder. Whisk thoroughly to distribute spices evenly throughout the flour mixture.
03 - Remove chicken from marinade, allowing excess liquid to drip off. Dredge each piece in flour mixture, pressing firmly to ensure thick, even coating. Place coated pieces on wire rack and let rest for 10 minutes to help coating adhere properly.
04 - Pour vegetable oil into deep fryer or large heavy-bottomed pot. Heat to 350°F, maintaining consistent temperature throughout frying process.
05 - Carefully lower chicken pieces into hot oil, working in batches to avoid overcrowding. Fry for 12 to 15 minutes, turning occasionally, until golden brown and crisp, and internal temperature reaches 165°F.
06 - Transfer fried chicken to wire rack or paper towels to drain excess oil. Let rest for 5 minutes before serving to allow juices to redistribute.