Start by placing the chicken cutlets in a bowl or zip-top bag. Pour in the dill pickle juice and buttermilk, ensuring the chicken is fully submerged. Seal and refrigerate for at least 1 hour. This marinade tenderizes the meat and infuses it with that unmistakable tangy flavor.
In a separate bowl, whisk together the flour, powdered sugar, paprika, salt, black pepper, garlic powder, and baking powder. This blend creates a flavorful, crispy coating that mimics the original sandwich's texture.
In another bowl, beat the egg until smooth. Remove the chicken from the marinade, allowing excess liquid to drip off. Dip each piece into the egg, then dredge thoroughly in the flour mixture, pressing gently to ensure the coating adheres well.
Heat peanut oil in a deep fryer or large skillet to 350°F (175°C). Carefully add the breaded chicken pieces, frying in batches to avoid overcrowding. Cook each piece for about 4-5 minutes per side, or until golden brown and the internal temperature reaches 165°F (74°C). Transfer to a paper towel-lined plate to drain excess oil.
Butter and toast the hamburger buns until golden. Place a few dill pickle slices on the bottom bun, add the crispy chicken, and top with the other half of the bun. Serve immediately for the best experience.