1. Craft the zesty remoulade sauce by whisking together all ingredients in a medium bowl. Taste and fine-tune seasonings. Chill sauce until serving time.
2. Slice green tomatoes into uniform 3/8-inch thick rounds using a serrated knife. Season both sides with coarse salt and let rest for half an hour to extract excess moisture, which enhances breading adhesion.
3. Prepare three distinct breading stations using shallow dishes:

First station: Blend flour with garlic powder, onion powder, and smoked paprika.

Second station: Combine buttermilk, egg white, and hot sauce.

Third station: Mix breadcrumbs and cornmeal.

1. Position a wire rack inside a rimmed baking sheet. Carefully coat each tomato slice by first dredging in seasoned flour, then dipping in buttermilk mixture, and finally rolling in breadcrumb-cornmeal blend. Press gently to ensure even coating.
2. Arrange breaded tomato slices on the rack in a single layer, allowing coating to set while preparing the cooking surface.
3. Heat cast iron skillet over medium-high heat until oil reaches 350 degrees fahrenheit, confirming readiness by testing with water droplets.
4. Gently introduce 3-4 breaded tomato slices to the hot oil, avoiding overcrowding. Fry until achieving a rich golden-brown color, approximately 3-5 minutes per side. Adjust heat as needed to maintain consistent temperature.
5. Transfer fried tomatoes to a paper towel-lined plate to drain excess oil. Continue frying remaining slices, replenishing oil if necessary.
6. Serve piping hot, accompanied by the chilled remoulade sauce for a delightful southern-inspired appetizer.