Add the flour and cornstarch to the remaining spice mixture in the bowl and whisk well to combine. In a separate medium bowl, place the buttermilk, egg whites, hot sauce, and alcohol and whisk thoroughly to combine.
Use one hand for the wet mixture and one hand for the dry, take 1 piece of chicken at a time, toss in the flour mixture, shaking off excess, dip chicken in the buttermilk mixture to completely coat, then place back in the flour mixture. Toss as needed to completely coat the chicken, pressing into it with your fingers. Repeat with remaining chicken.
Set aside at room temperature for at least 10 minutes (up to 30 minutes) while you set up for frying and heat the oil.
Place the oil in a large Dutch oven or deep, heavy-bottom pan, attach a candy or deep-fry thermometer, and heat over medium-high heat until the oil is 360°F, about 15 minutes. Set up your serving plates nearby with pieces of white bread. This is where the cooked chicken will land.