01 - Whisk buttermilk with salt, garlic powder, onion powder, cayenne, and black pepper in a large bowl. Submerge chicken pieces completely in the marinade. Cover bowl and refrigerate for minimum 2 hours, ideally overnight for maximum flavor penetration.
02 - Combine flour, paprika, salt, black pepper, cayenne, and baking powder in a separate bowl. Mix 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 rest for 10 minutes to set coating.
04 - Pour vegetable oil into deep fryer or large heavy pot. Heat to 350°F, maintaining consistent temperature throughout frying process.
05 - Lower chicken pieces into hot oil in small batches, avoiding overcrowding. Fry for 12–15 minutes, turning occasionally, until exterior is deep 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.