Slice chicken breasts into sandwich-sized fillets and place them in a bowl. Combine buttermilk, hot sauce, paprika, garlic powder, onion powder, Cajun seasoning, salt, and pepper. Pour over chicken and marinate for at least 1 hour in the refrigerator for maximum flavor.

In a shallow dish, combine flour, corn starch, paprika, garlic powder, onion powder, Cajun seasoning, and salt & pepper.

Heat oil in a deep skillet or fryer to 350°F (175°C).

Remove marinated chicken from the wet batter, letting excess drip off. Coat in the dry batter, pressing gently.

Fry chicken fillets in batches for 4–6 minutes per side until golden brown, then drain on paper towels.

In a small bowl, mix mayo, hot sauce, and Cajun seasoning to create a zesty spread.

Lightly toast brioche buns. Spread the spicy mayo on both halves, add pickles, and top with fried chicken fillets.

Serve immediately while hot and crispy.