Preheat oven to 425°F. Line a sheet pan with foil and set a greased rack on top.
Whisk buttermilk with 2 tbsp hot sauce in a bowl. Add chicken and chill 15 minutes.
Toss panko with 1 tbsp olive oil in a shallow dish. Mix flour, cornstarch, salt, pepper, garlic, onion, and paprika in another.
Drain chicken well. Dredge pieces in the flour mixture, shaking off excess.
Press each piece into the oiled panko until fully coated.
Arrange on the rack, leaving space. Drizzle remaining 1 tbsp oil over the tops.
Bake 16–18 minutes, turning once, until crunchy and 165°F inside.
Melt butter. Whisk with 1/3 cup hot sauce and honey. Toss hot chicken with sauce and serve with dressing.