In a large bowl, combine buttermilk with 1 tablespoon salt and 1 teaspoon black pepper. Add chicken pieces and turn to coat completely. Cover and refrigerate for at least 4 hours or overnight.

In a shallow dish, whisk together flour, paprika, garlic powder, onion powder, cayenne pepper, remaining salt, and black pepper.

Remove chicken from buttermilk marinade, allowing excess to drip off but keeping chicken moist.

Dredge each piece in the seasoned flour mixture, pressing firmly to adhere. Shake off excess.

Dip chicken back into buttermilk briefly, then dredge again in flour mixture for a double coating.

Let coated chicken rest on a wire rack for 15 minutes to set the coating.

In a large cast-iron skillet or heavy-bottomed pan, heat vegetable oil to 325-350°F, about 2 inches deep.

Carefully add chicken pieces without crowding, starting with dark meat as it takes longer to cook.

Fry for 12-15 minutes per side for large pieces, 8-10 minutes for smaller pieces, turning once until golden brown and internal temperature reaches 165°F.

Remove chicken and drain on a wire rack over paper towels. Let rest 5 minutes before serving.