Whisk buttermilk, hot sauce, and 1/2 teaspoon salt in a large bowl. Add chicken thighs, turning to coat. Cover and refrigerate at least 2 hours or up to overnight. The buttermilk tenderizes the meat and the hot sauce seasons it throughout.

Combine honey, red pepper flakes, and vinegar in a small saucepan over low heat. Warm gently for 5 minutes until fragrant and the honey thins slightly. Do not boil. Remove from heat and let steep while you fry the chicken. The longer it sits, the spicier it gets.

In a shallow dish, whisk flour, garlic powder, paprika, remaining 1 teaspoon salt, and black pepper. Remove chicken from buttermilk, letting excess drip off. Dredge each piece in the flour mixture, pressing firmly so the coating adheres. Shake off excess.

Heat oil in a large heavy skillet to 350 degrees F. Working in batches to avoid crowding, fry chicken for 5-6 minutes per side until deep golden brown and an instant-read thermometer registers 165 degrees F in the thickest part. Transfer to a wire rack set over a baking sheet to drain. Let oil return to 350 degrees F between batches.

Spread cut sides of toasted buns with butter. Place fried chicken on bottom buns, drizzle generously with warm hot honey, top with pickle chips, and cap with bun tops. Serve immediately while the chicken is crisp and the honey is loose.