Place chicken pieces in a large casserole pan. Mix buttermilk and red hot sauce, if using, with salt and pepper in a large measuring cup, and then pour buttermilk mixture over top of the chicken. Cover and refrigerate for at least 4 hours, preferably overnight for about 8 hours.
Remove from refrigerator about 20 to 30 minutes before frying.
Mix the flour, salt, white pepper, smoked paprika, sugar, and brown sugar in a large bowl. Set aside.
Preheat oil for frying. You can use a deep fryer, or a large deep pan filled halfway up with oil. I typically use 2 large, deep frying pans for one batch so it all finishes at the same time and my pans won't be over-crowded. Bring the oil to a bubble over medium heat.
Start taking the pieces of chicken out of the buttermilk and then dunk each one in the flour mixture, making sure to coat on each side. Place each piece carefully in the pan of oil. Repeat until all the chicken is in your pans. You can then discard any remaining buttermilk and flour mixture.
Cook the chicken for about 8 to 10 minutes, flipping with long tongs to ensure all sides are cooked evenly. Now reduce heat to low, cover the pans and allow chicken to simmer for about 25 to 30 minutes, making sure to flip at least 2 to 3 times during the process. Uncover the pans and allow to cook for about 5 more minutes to really crisp the chicken up.
Remove pieces carefully with tongs and place on paper towel lined plates. You can dab off excess grease if you like.
Serve with a big old "I can make my own dang chicken at home from now on" smile!