Refrigerate chicken in buttermilk and hot sauce for 4 hours; drain 5 minutes.

Heat oil in a deep, heavy pot to 325°F. Mix flour, paprika, cayenne, garlic powder, and salt.

Press thighs into flour mixture. Moisten surfaces with a spoonful of marinade; dredge again for craggy patches.

Fry 2 pieces at a time for 12 to 15 minutes, turning twice, until deeply browned and 165°F at thickest part, measuring away from bone.

Rest on a rack 8 minutes to set crust without steaming on paper towels.