1Place buttermilk in a large, shallow nonreactive dish and add chicken. Cover and refrigerate for at least 2 hours or overnight.
2Combine flour, paprika, cayenne, garlic powder, salt, and pepper in a large plastic bag.
Remove chicken pieces from buttermilk and add to bag with flour mixture. Shake to coat; dust off excess.
3Pour 3/4" peanut oil into a heavy skillet. Heat oil over medium-high heat until it registers 350° on a deep-fry thermometer. Reduce heat to medium and add the chicken pieces, a few at a time. Fry each piece for 10-12 minutes, turning occasionally, until it is crispy and golden and internal temperature registers 165° on an instant-read thermometer. Drain on paper towels; serve.