Whisk buttermilk, hot sauce, 4 minced garlic cloves, and 1 tsp salt in a large bowl. Add chicken, coat well, cover, and refrigerate at least 30 minutes (up to 8 hours).

Melt butter in a small saucepan over low heat. Add remaining 3 minced garlic cloves and a pinch of salt, cook gently 2 minutes until fragrant. Stir in 1 tbsp parsley and set aside.

In a shallow dish, whisk flour, cornstarch, garlic powder, onion powder, smoked paprika, 1 tbsp salt, pepper, and cayenne.

Heat 2 inches of oil in a heavy pot to 350°F (175°C). Remove chicken from marinade, let excess drip off, then dredge in flour mixture, pressing coating on. Fry in batches, skin‑side down, 7 to 8 minutes per side, until deep golden and internal temp at thickest part reads 165°F (74°C). Drain on a wire rack.

Toss hot chicken in a bowl with the warm garlic butter until slick. Scatter extra parsley over the top and serve immediately.