01 - In a bowl, whisk together mayonnaise, Dijon mustard, hot sauce, horseradish, pickle relish, smoked paprika, lemon juice, and garlic. Season with salt and pepper. Cover and refrigerate until ready to use.
02 - In a shallow dish, mix flour, cornmeal, Cajun seasoning, garlic powder, paprika, salt, and black pepper. In a separate bowl, beat eggs with buttermilk.
03 - Pat shrimp dry. Dip each shrimp first in the egg mixture, then dredge in the seasoned flour-cornmeal mix, shaking off excess.
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 and cooked through. Drain on paper towels.
05 - Toast the bread rolls lightly. Slice open without cutting all the way through.
06 - Generously spread remoulade sauce on both sides of each roll. Layer with lettuce, tomato slices, fried shrimp, and pickles.
07 - Serve immediately while shrimp are hot and crispy.