Preheat your oil (in fryer or skillet) to 375˚.
In shallow bowl mix together flour, cornmeal, garlic & onion powders, cayenne, salt and pepper.
In a second shallow dish mix together milk and eggs.
Dip shrimp into the milk mixture and then coat in the flour mixture.
Once coated fry for a couple of minutes, until shrimp is golden brown and cooked all the way through.
Remove from oil and place on a paper towel to dry.
While shrimp is frying whisk together all of the remoulade ingredients.
Toast bread in oven. In a small bowl mix together butter and garlic powder and brush on toasted bread.
To build sandwich lay tomato on bottom bun, place shrimp on next, pour remoulade over shrimp, top with lettuce and close with top bun.