In a large mixing bowl, whisk together buttermilk and hot sauce until smooth. Stir in garlic powder, onion powder, smoked paprika, black pepper, and kosher salt. Submerge chicken pieces in the marinade, cover, and refrigerate for at least 2 hours, ideally overnight.

In a separate bowl, combine all-purpose flour, cornstarch, cayenne pepper, smoked paprika, dried oregano, thyme, cumin, chili powder, and salt. Whisk until well blended.

Remove chicken from marinade, allowing excess to drip off. Dredge each piece in the flour mixture, making sure it is well-coated. Shake off excess flour and set aside on a wire rack.

Heat vegetable oil in a deep skillet or heavy pot to 350°F. Fry chicken pieces for 12-15 minutes, turning occasionally, until golden brown and internal temperature reaches 165°F.

Remove chicken from oil and drain on a wire rack or paper towels. Let rest for a few minutes before serving.