01 - Whisk buttermilk with salt, garlic powder, onion powder, cayenne, and black pepper in a large bowl. Submerge chicken pieces completely. Cover and refrigerate minimum 2 hours, preferably overnight.
02 - Combine flour, paprika, salt, black pepper, cayenne, and baking powder in a separate bowl. Mix thoroughly to distribute spices evenly.
03 - Lift chicken from marinade, allowing excess liquid to drip off. Press each piece firmly into flour mixture, ensuring thick, even coating. Arrange on rack and rest 10 minutes.
04 - Pour oil into deep fryer or heavy pot. Heat to 350°F, monitoring with thermometer for accuracy.
05 - Lower chicken pieces into hot oil in small batches. Fry 12–15 minutes, turning occasionally, until golden brown and crisp with internal temperature reaching 165°F.
06 - Transfer fried chicken to wire rack or paper towels. Let rest 5 minutes before serving to maintain crispiness.