Pour buttermilk, hot sauce, and cayenne pepper into a large bowl and add chicken. Make sure that chicken is fully submerged in the buttermilk. Cover with plastic wrap or a lid and allow chicken to soak in buttermilk mixture for 4 hours (up to overnight) in the refrigerator.
Remove chicken from the buttermilk and pat dry with paper towels – save the buttermilk.
Add seasonings to the chicken. (there’s not real measurement of each just coat both sides of the chicken with them, light on the red pepper flakes and rosemary and heavy on the garlic salt, onion powder, and smoked paprika. Trust me, you can’t go wrong) Let the seasonings sit on the chicken for about 20 minutes.
In a shallow dish, combine flour and cornstarch and the seasonings.
Heat oil over medium heat in a deep skillet or pot, oil should be about 4-5 inches deep in the pan. Heat to roughly 360-380 degrees Fahrenheit.
Grab the bowl of buttermilk and set it next to the seasoned flour mixture. Dredge marinated chicken pieces into the flour mixture, dip it into the buttermilk, and then back into the flour mixture – make sure the chicken is doused in flour, none of the meat should be exposed.
After dredging the chicken, place chicken on a wire rack and let it sit for about 5 minutes.
Fry 2-3 piece of chicken at a time and let the chicken cook until crispy and golden brown, about 10-15 minutes. Cooking time will vary with the thickness of the meat. To ensure chicken is thoroughly cooked, use a meat thermometer to ensure the internal temperature of the chicken is 165 degrees F.
Use tongs to remove the chicken from the oil and let the cooked chicken rest on a cooling rack or paper towels.
Add chicken to a large plate. Chop up some scallions and sprinkle over top of chicken.
Eat! :)