Begin by marinating the chicken. In a bowl, whisk together the buttermilk and 1 tablespoon of hot sauce. Add the chicken pieces, ensuring they are fully submerged. Cover and refrigerate for at least 4 hours, or preferably overnight, to tenderize and infuse flavor.

Prepare the dredging station. In a shallow dish or large zip-top bag, combine the flour, smoked paprika, 1 tablespoon cayenne pepper, garlic powder, onion powder, salt, and black pepper. Mix well.

Heat the frying oil. In a deep fryer or a heavy-bottomed pot, heat about 3-4 inches of vegetable oil to 350°F (175°C). Use a thermometer to ensure accurate temperature.

Dredge the chicken. Remove chicken pieces from the buttermilk marinade, letting any excess drip off. Dredge each piece thoroughly in the flour mixture, pressing to ensure a good coating. Set aside on a plate.

Fry the chicken. Carefully place 2-3 chicken pieces into the hot oil, being careful not to overcrowd the pot. Fry for about 12-15 minutes, turning occasionally, until golden brown and cooked through (internal temperature should reach 165°F or 74°C). Remove chicken with tongs and place on a wire rack set over a baking sheet to drain.

While the chicken is frying, prepare the hot sauce mixture. In a small saucepan over low heat, melt the butter. Stir in the 1/4 cup cayenne pepper, brown sugar, paprika, garlic powder, and salt. Whisk until smooth and well combined. Keep warm.

Assemble the Nashville hot chicken. Once all chicken pieces are fried and drained, brush them generously with the warm cayenne butter mixture. For an extra kick, you can drizzle more of the cayenne oil from the bottom of the saucepan over the chicken.

Serve immediately while hot and crispy.