Combine chicken pieces with black pepper, salt, paprika, rosemary, thyme, oregano, sage, white pepper, and cayenne in a large bowl or resealable plastic bag to coat.
Add buttermilk to fully coat chicken. Refrigerate for at least 6 hours.
Combine flour, salt, paprika, cayenne, garlic powder, white pepper, and onion powder in a large resealable plastic bag or shallow dish.
Remove chicken from the buttermilk and and shake to remove any excess. Dredge each piece in the seasoned flour. Shake off any excess and transfer to a plate.
Heat cooking oil in a large Dutch oven to 350 degrees F. Add the white meat pieces of chicken to the pan and cook for 16-18 minutes, turning halfway through. Remove chicken from the oil and transfer to a cooling rack set over a paper towel lined baking sheet. To keep warm, set on baking dish, tent with foil, and keep warm in 200 F degree oven.
Allow oil to once again heat to 350 degrees F. Add the dark meat pieces of chicken to the pan and cook for 18-25 minutes, turning halfway through. Remove chicken from the oil and transfer to a cooling rack set over a paper towel lined baking sheet.