In a large bowl, combine the marinade ingredients. Add the chicken and toss in the marinade. Cover the bowl and refrigerate for 12 to 24 hours.
Combine all the ingredients for the seasoned flour in a large bowl and whisk to combine.
In a large Dutch oven or heavy-bottomed pot, heat the oil to 350 F, leaving 5 inches or more of empty space at the top of the pot. Note: It is best to use a candy thermometer to regulate your heat. Try to maintain a 350 F temperature the entire time, raising and lowering the heat as needed.
Heat the oven to 300 F.
Remove the chicken from the buttermilk marinade, one piece at a time, and let any excess marinade drip off. Toss the chicken pieces in the seasoned flour until they are completely coated, shaking off any excess flour. Place the chicken on a sheet pan lined with a wire rack, and continue this process until all of the chicken pieces have been breaded.
One piece at a time, dip the breaded chicken back into the buttermilk mixture briefly, allowing any excess to drip off; then toss it in the seasoned flour one more time. Place the chicken back on the wire rack.
Working in batches and using metal tongs, gently place 2 to 3 pieces of chicken in the hot oil, turning occasionally until the chicken is a dark golden brown color, about 10 minutes. Then place the fried chicken on a clean rack.
Repeat until all of the chicken has been fried. Transfer the sheet pan with all of the fried chicken to the oven and bake, turning occasionally, until the internal temperature of the largest piece of chicken is 165 F.
Let the chicken rest for a couple of minutes, then serve hot.