Pound the chicken breasts lightly and trim any extra fat off.

In a small bowl, stir together the Cajun seasoning, pepper, garlic powder, onion powder, and sugar.

Add 1 tablespoon of the seasoning mix to the buttermilk and stir to combine. Pour over the chicken. Marinate for at least 1 hour or overnight.

Combine remaining seasoning with flour. Whisk to mix.

Add 3 to 4 tablespoons of the buttermilk marinade into the flour mix, keeping some chunky pieces.

Dredge the chicken in the flour mixture, dip back into buttermilk, then dredge again, pressing chunky flour into the chicken.

Heat oil in a deep pan over medium-high heat until a little flour sizzles upon contact.

Fry chicken pieces for 5-6 minutes on each side until golden and cooked through (165°F).

Remove fried chicken and drain on a cooling rack. Repeat with remaining chicken.

Assemble sandwiches by placing chicken on toasted buns and adding mayonnaise and pickles if desired.