In a container large enough to fit all your chicken, combine all the ingredients for buttermilk marinade, mixing until everything is combined.
Place chicken in container, seal, and let marinate for 6 to 24 hours.
Once chicken has marinaded, remove from the fridge and allow to warm for at least 30 minutes before frying.
While chicken is warming up, in a small skillet, add enough vegetable oil to cover about 3/4 of a piece of chicken.
Using an oil/candy thermometer, heat the oil to 350F (A thermometer is a must, you can purchase them relatively cheap, and they make the deep frying process MUCH safer, and assures you cook your chicken evenly without burning!).
While the oil is heating, and the chicken is coming to room temperature, prepare your breading.
In a container, combine ingredients for the breading, and shake with lid on to combine.
Once chicken has warmed, place the chicken one at a time into the breading container.
Shake the chicken in the container to fully coat with breading mix, repeat with the rest of the chicken.
Once all your chicken is breaded, begin frying.
Fry the chicken in batches, and don't overcrowd the pan.
The oil temperature will drop a bit, but don't change the temperature on the stove, it will come back up as the chicken cooks.
Cook the chicken until the internal temperature reaches 165F.
Once the chicken has fried, remove it to a wire cooling rack with paper towel beneath it. Dab any excess grease off the chicken with paper towel.
Allow chicken to cool before serving. If chicken gets too cold while the other chicken is frying, reheat it in the oven at 350F for about 5 minutes.