Add your chicken to a large bowl then add in the buttermilk and all of the seasonings including the seasoned salt, paprika, and  garlic powder.

Cover the bowl with a lid or with plastic wrap and place it in the refrigerator for at least an hour or overnight.

While the chicken is marinating, make your dry flour mixture by combining the flour, cornstarch, and seasonings in a large bowl or Ziploc bag. Mix the seasonings into the flour until everything is thoroughly combined. 

Remove the chicken from the refrigerator and begin breading it. Take one piece of chicken out of the buttermilk and let the excess marinade drain off, then place it in the flour mixture and coat every side evenly with the flour. Be sure to sort of press the flour into the chicken.

Once the chicken is fully coated with the flour, place it out on a wire rack and let it set for at least 10 minutes so that the flour breading can set in before frying. Continue to bread the other pieces of chicken the same way. Discard the remaining buttermilk and flour mixture when you are finished.

While the breading is setting on the chicken, heat up your vegetable oil in a cast iron skillet over medium heat, until it reaches 375°F.

Gently place your chicken in the hot oil, careful not to overcrowd the skillet. You may have to fry in batches. 

Fry each piece of chicken on each side for 7-10 minutes until they are golden brown. Remove them from the skillet and set them out on a clean wire rack to drain the excess oil.

Each piece of chicken should reach an internal temperature of 165°F, or should have no pink juices flowing out of them. That is how you know they are cooked all the way through. Serve right away, and enjoy!