Mix buttermilk and spices. Add chicken. Marinate minimum 1 hour, refrigerated.
Whisk flour and cornstarch in a shallow bowl.
Remove chicken from marinade, press firmly into dredge on all sides. Rest on wire rack 10 minutes.
Heat oil to 350°F. Fry each piece 4 to 5 minutes per side until golden and internal temp reads 165°F.
Whisk hot sauce, melted butter, honey, and garlic powder together. Warm briefly. Toss hot chicken in sauce immediately.
Toast buns. Spread dressing on bottom. Layer chicken, pickles, lettuce. Serve right away