In a large bowl, combine the chicken pieces, buttermilk, and hot sauce. Ensure the chicken is fully submerged. Cover and refrigerate for at least 4 hours, or overnight.

In a large shallow dish or heavy-duty paper bag, whisk together the flour, cornstarch, salt, pepper, paprika, garlic powder, onion powder, and cayenne.

Remove chicken from the buttermilk, letting excess drip off. Dredge each piece in the flour mixture, pressing firmly to adhere.

For extra crunch, dip the floured chicken back into the buttermilk and then back into the flour (double dredge).

Place the coated chicken on a wire rack and let it rest for 15-20 minutes. This is crucial for the crust to set.

Fill a large cast-iron skillet or deep pot with about 2 inches of oil. Heat to 350°F (175°C).

Carefully add chicken pieces to the oil, being careful not to overcrowd the pan. Fry in batches if necessary.

Fry in batches, turning as needed. Cook until the crust is golden and every piece reaches 165°F (74°C), checking thick pieces near the bone; frying time varies by cut and size.

Drain the chicken on a wire rack over a paper-towel-lined tray. Let rest for 5-10 minutes before serving.