Whisk together buttermilk and hot sauce in a bowl and marinate chicken tenders for 30 minutes.
In a separate shallow dish, combine all-purpose flour and salt.
Dredge each tender in flour, dip back into the buttermilk marinade, and dredge in flour a second time to ensure a heavy coating.
Heat vegetable oil in a heavy-bottomed pot or deep fryer to 350 degrees Fahrenheit.
Fry chicken tenders in batches for 4 to 5 minutes until the crust is golden brown and the internal temperature reaches 165 degrees Fahrenheit.
Whisk together cayenne pepper, brown sugar, chili powder, garlic powder, and smoked paprika in a heat-safe bowl.
Carefully ladle 1/2 cup of the hot frying oil into the spice mixture and whisk until well combined.
Brush the spicy oil glaze immediately over the fried tenders while they are still hot.