01 - Whisk together mayonnaise, Dijon mustard, hot sauce, horseradish, pickle relish, smoked paprika, lemon juice, and garlic in a bowl. Season with salt and pepper. Cover and refrigerate until ready to use.
02 - Mix flour, cornmeal, Cajun seasoning, garlic powder, paprika, salt, and black pepper in a shallow dish. In a separate bowl, beat eggs with buttermilk until combined.
03 - Pat shrimp dry with paper towels. Dip each shrimp first into the egg mixture, then dredge thoroughly in the seasoned flour-cornmeal mixture, shaking off excess breading.
04 - Heat 2 inches of vegetable oil in a deep skillet or Dutch oven to 350°F. Fry shrimp in batches for 2-3 minutes, turning once, until golden brown and cooked through. Drain on paper towels.
05 - Lightly toast the French bread rolls. Slice open each roll without cutting all the way through, creating a hinge.
06 - Generously spread remoulade sauce on both sides of each roll. Layer with shredded lettuce, tomato slices, fried shrimp, and dill pickle chips.
07 - Serve promptly while shrimp remain hot and crispy for the best texture and flavor experience.