Cut the whole chickens into 4 breasts, 4 thighs, 4 legs, and 4 wings. Set aside.
Preheat your oil to 325 degrees F, either in a heavy pan or cast iron skillet on the stove or in a deeper fryer. As long as your oil is between 300 and 350 degrees Fahrenheit, your chicken should come out perfect.
In a large bowl, combine flour, salt, black pepper, paprika, garlic powder, onion powder, and cayenne pepper. Set aside.
Pour the buttermilk into a separate large bowl, making sure its deep enough for the chicken to be submerged.
Prepare your dredging station. Place your chicken in a bowl. Beside that, your dry mixture.
Take the chicken breasts and dust them with the flour mixture. Then, dip them in buttermilk until they are coated.
Place in the flour mixture and push the flour mixture into the chicken. Make sure the chicken is thoroughly coated. When coating and breading your chicken, make sure to tap off the excess buttermilk and flour.
Gently place the chicken breasts in the hot oil.
Next, repeat the dredging steps with your other pieces of chicken: thigh, leg, then wing.
When you place the last wing into the fryer, you should have 16 pieces of chicken in the oil. Set a timer for 15 minutes. Flip several times to ensure the breading cooks evenly and does not burn. If you are pan frying, do the pieces in several batches, as overcrowding the pan may cause the breading to fall off.
After 15 minutes, take a meat thermometer and check the temperature of a breast. If it reads 165 degrees F, the chicken is done. With fried chicken, white meat will be best around 165 F and dark meat can be cooked to 170 F for ideal texture.
Remove the chicken pieces from the pan or fryer and drain for 5 minutes. Let it cool for another 10 minutes before serving.