Make spicy mayo by combing mayonnaise with hot sauce and paprika.
Cut each chicken breast into two equal-size pieces. Pound the chicken on each side.
In a large bowl combine together buttermilk with paprika, garlic salt and black pepper. Whisk to combine together. Add chicken to the marinade and leave it in a fridge for at least 30 minutes, up to 24 hours.
In a separate bowl combine flour together with corn starch and spices. Once combined, drizzle a few spoonfuls of buttermilk to the mix.
In a separate bowl combine flour together with corn starch and spices. Once combined, drizzle a few spoonfuls of buttermilk to the mix. Dredge each chicken piece into the flour.
Preheat a heavy bottom pan with oil to 350 °F. Fry the chicken until all sides are golden brown and the internal temperature of the chicken reaches 165 °F.
To build the Popeyes sandwich, apply spicy mayo on both sides of the the bun. Top the bottom bun with pickle slices and crispy chicken and cover it with the top bun.
Serve right away, while the chicken is still hot and crispy.