Marinate the Chicken: Whisk buttermilk and hot sauce in a bowl. Submerge the chicken fillets and refrigerate for at least 30 minutes to tenderize.
Prepare the Breading: In a shallow dish, mix flour, cornstarch, and seasonings. Remove the chicken from the buttermilk, letting excess drip off, then coat thoroughly in the flour mixture, pressing it in for a crispy crust.
Fry the Chicken: Heat oil to 350°F (175°C) in a deep skillet. Fry the chicken fillets for 4-5 minutes per side until golden brown and cooked through. Drain on a wire rack or paper towel-lined plate.
Make the Hot Honey: In a saucepan over low heat, combine honey, hot sauce, cayenne, and red pepper flakes. Stir until well blended, adding butter for extra richness if desired.
Assemble the Sandwiches: Toast brioche buns, spread with mayonnaise or aioli, and place a crispy chicken fillet on top. Drizzle generously with hot honey, add lettuce and pickles if using, then top with the bun.
Serve & Enjoy! Enjoy immediately with your favorite sides like fries or coleslaw!