In a large bowl, whisk together 2 tablespoons of Cajun seasoning, mustard, hot sauce, buttermilk, and eggs until combined.
Add in the shrimp and mix well until coated. Let marinate in the fridge for 30 minutes.
Pour some oil into a large frying pan and heat to 350°.
Add the flour, cornmeal, remaining 2 tablespoons of Cajun seasoning, and salt to taste to a casserole-size pan and whisk until combined. Taste it to make sure it’s seasoned enough.
Remove the shrimp from the refrigerator and add a handful to the pan with the flour-cornmeal mixture.
Toss very well to make sure it is coated on all sides.
Set aside on a sheet tray lined with parchment paper and repeat the process until all the shrimp have been coated in the batter.
Add half the shrimp to the hot oil and cook for 2 to 3 minutes or until golden brown and the shrimp are cooked through. Do not overcook.
Set the shrimp on a sheet tray with a rack to drain any excess oil. Repeat the process with the remaining half of the battered shrimp.
Spread some butter on each half of the sliced French bread.
Toast the bread butter on a flat top or in a pan over low to medium heat until brown and toasted.
Place some lettuce down on the bottom toasted slices of bread.
Next, evenly spread the tomatoes and pickles.
Place on as many shrimps as you can.
Spread a generous helping of the mayonnaise or remoulade on the top slice of bread and then add it to the top of the sandwich.
Notes
Make-Ahead: This is meant to be eaten as soon as it is removed from the frying oil.How to Store: Cover the shrimp separately from the other ingredients and store it in the refrigerator for up to 3 days. Cover and freeze the shrimp once they are cooked for up to 3 months. Go directly from the freezer to the oven and evenly spread them out on a cookie sheet tray lined with parchment paper at 375° for 12-15 minutes or until hot, crispy, and cooked through.How to Reheat: Place the desired amount of pre-fried shrimp evenly spread on a cookie sheet tray lined with parchment paper and bake at 375° for 4-6 minutes or until hot and crispy. Serve as a sandwich with the other recommended ingredients.Any size of shrimp can be used in this recipe.You can also use your favorite Cajun or blackened seasoning.When making the marinade, feel free to taste it before adding the eggs to ensure it is flavorful enough to season up the shrimp.I like to use peanut or vegetable oil for frying.