Step 1: Marinate the Chicken

• In a medium bowl, mix buttermilk, salt, black pepper, garlic powder, and smoked paprika.
• Place the chicken fillets in the buttermilk mixture and let marinate for at least 1 hour (or overnight for maximum tenderness). If short on time, even 15-30 minutes will help.

Step 2: Make the Spicy Mayo Sauce

• In a small bowl, whisk together mayonnaise, Dijon mustard, hot sauce, honey, lemon juice, smoked paprika, and garlic powder.
• Taste and adjust spice levels if needed.
• Cover and refrigerate until ready to use.

Step 3: Prepare the Slaw

• In a bowl, mix shredded cabbage, shredded carrots, apple cider vinegar, mayonnaise, salt, and black pepper.
• Toss well to coat and let sit for at least 10 minutes to absorb flavors.

Step 4: Coat the Chicken

• In a large bowl, whisk together flour, cornstarch, salt, black pepper, smoked paprika, garlic powder, and cayenne pepper.
• In a separate bowl, whisk together 1 egg and ¼ cup buttermilk.
• Remove a chicken fillet from the buttermilk marinade, letting excess drip off.
• Dredge in the flour mixture, then dip into the egg mixture, and then coat again in the flour mixture (this double-coating method creates extra crunch).
• Place on a wire rack and repeat for all fillets.

Step 5: Fry the Chicken

• Heat about 1 inch of oil in a deep skillet or frying pan to 350°F (175°C).
• Fry the chicken fillets in batches for 4-5 minutes per side, until golden brown and crispy.
• Transfer to a wire rack to drain excess oil.

Step 6: Toast the Brioche Buns

• Heat a pan over medium heat and melt 2 tablespoons of butter.
• Place the brioche buns cut-side down in the pan and toast until golden brown.

Step 7: Assemble the Sandwich

• Spread spicy mayo sauce on both sides of the toasted brioche bun.
• Place the crispy fried chicken fillet on the bottom bun.
• Add a scoop of slaw and sliced pickles (if using).
• Top with the other half of the bun, press gently, and enjoy!