Start by adding cornmeal, breadcrumbs, & seasonings to a bowl. Stir until combined. Set aside.
Heat oil until it reaches 350°
While oil is heating, season fish filets, then add some mustard to lightly coat the fish. You won't taste the mustard but it'll help keep the cornmeal coating on the fish.
Add fish to cornmeal mixture pressing it into the mixture ensuring that it is fully coated.
Once fish is coated, fry in oil until golden brown. Be sure not to over crowd your pan. Remove fish & place on a wire rack. Keep warm in oven until all fish is cooked.
Assemble your sandwiches with toppings of your choice. I chose a spicy remoulade sauce (recipe is available), lettuce & tomato. I served mine alongside some French fries.