01 - In a bowl, whisk buttermilk and hot sauce. Add chicken breasts, cover, and marinate in the refrigerator for at least 30 minutes (up to 4 hours for more flavor).
02 - In a separate bowl, mix flour, cornstarch, paprika, garlic powder, onion powder, cayenne, salt, and black pepper.
03 - Remove chicken from marinade, letting excess drip off. Dredge each piece in the flour mixture, pressing to coat well.
04 - In a large skillet or deep fryer, heat about 1 inch of oil to 350°F. Fry chicken breasts for 4-5 minutes per side, until golden brown and cooked through (internal temp 165°F). Drain on paper towels.
05 - For the sauce: In a small bowl, combine mayonnaise, sour cream, Dijon mustard, honey, lemon juice, hot sauce, smoked paprika, salt, and pepper. Mix until smooth and refrigerate until ready to use.
06 - To assemble: Spread sauce on the bottom half of each toasted bun. Add lettuce, fried chicken breast, tomato slices, and pickles. Top with bun lid. Serve immediately.