Prepare the shrimp by patting them dry and seasoning with salt and pepper.
In a bowl, whisk together buttermilk, cayenne, and garlic powder. Soak the shrimp in this mixture for at least 30 minutes.
Set up a dredging station with flour in one bowl and additional seasoning for extra flavor.
Heat vegetable oil in a large skillet to 350°F (175°C).
Remove shrimp from buttermilk, allowing excess to drip off, and dredge in flour mixture until fully coated.
Carefully place shrimp in the hot oil, frying in batches to avoid overcrowding.
Fry shrimp for 2-3 minutes per side until golden brown and crispy. Remove and drain on paper towels.
Slice the French rolls and spread a generous amount of remoulade sauce on each half.
Layer shredded lettuce and tomato slices on the bottom half of the roll.
Top with the crispy fried shrimp and finish with the top half of the roll.