Preparation of the Remoulade Sauce: In a medium-sized bowl, combine all the ingredients for the remoulade sauce. Mix well, ensuring even distribution of ingredients. Adjust seasonings if necessary. Once combined, refrigerate until it is to be served.
Tomato Preparation: With the use of a serrated knife, slice the green tomatoes into approximately 3/8-inch thick portions. Ensure uniformity in thickness for even cooking. Once sliced, sprinkle both sides of each slice with coarse salt. Allow these slices to rest for 30 minutes, which facilitates the removal of excess moisture. Subsequently, gently pat each slice dry using paper towels.
Breading Preparation: Arrange three shallow dishes, ideally pie plates. For the first dish, combine the flour, garlic powder, onion powder, and smoked paprika, ensuring they are well-mixed. For the second dish, whisk together the buttermilk, egg white, and hot sauce until well combined. For the third dish, combine the breadcrumbs and cornmeal thoroughly.
Breading the Tomato Slices: Place each tomato slice in the flour mixture, ensuring both sides are covered and shaking off any excess. Then, dip the flour-covered slice into the buttermilk mixture, ensuring even coating. Lastly, coat the slice in the breadcrumb-cornmeal combination, pressing gently to ensure adherence. Once breaded, place the tomato slices on a wire rack, ensuring no overlap.
Setting the Breading: Allow the breaded tomato slices to sit, which ensures the breading sets and adheres well during the frying process.
Oil Preparation: In a large cast iron skillet, heat the vegetable oil over medium-high heat until it reaches approximately 350 degrees Fahrenheit. Ensure the oil is shimmering but not smoking.
Frying the Tomato Slices: Carefully place 3 to 4 breaded tomato slices into the hot oil, ensuring they are not overcrowded. Fry until each side is a golden-brown color, typically 3 to 5 minutes per side. Adjust the heat as necessary to prevent overheating.
Post-Frying Process: Once fried to the desired color, transfer the tomato slices to a plate lined with paper towels to remove excess oil.
Serving: The fried green tomatoes are best served immediately. Accompany them with the previously prepared remoulade sauce.