In a large Dutch oven, pour oil to a depth of 3 inches, and heat over medium heat until a deep-fry thermometer registers 325°.
In a medium bowl, whisk together flour, cornmeal, Creole seasoning, and baking powder. In a small bowl, place buttermilk.
Working in batches, dredge shrimp in flour mixture, shaking off excess. Dip in buttermilk, letting excess drip off. Dredge in flour mixture, gently pressing to adhere. Fry shrimp in hot oil until golden brown, 2 to 3 minutes. Let drain on prepared rack.
Spread cut side of rolls with desired amount of Lemon Rémoulade. Top with fried shrimp, tomato slices, pickle slices, lettuce, and onion. Serve immediately.
Recipe by Louisiana Cookin' at https://louisianacookin.com/fried-shrimp-mini-po-boys-with-lemon-remoulade/