In a mixing bowl, combine mayonnaise, spicy brown mustard, paprika, fresh parsley, prepared horseradish, lemon juice, Cajun seasoning, pickle juice, hot sauce, and minced garlic. Stir well until all ingredients are fully blended. Cover the bowl with plastic wrap and refrigerate for at least 30 minutes.

Wash the green tomatoes thoroughly and slice them into ⅜-inch thick rounds. Sprinkle coarse salt generously over both sides of the slices and let them sit on a wire rack for 30 minutes.

Set up three shallow dishes. In the first dish, mix all-purpose flour with salt, smoked paprika, garlic powder, onion powder, and black pepper. In the second dish, whisk together buttermilk, egg white, and hot sauce. In the third dish, combine panko breadcrumbs and cornmeal.

Dredge each salted tomato slice first in the flour mixture, then in the buttermilk mixture, and finally press into the panko and cornmeal mixture. Place breaded slices on the wire rack to rest for about 10 minutes.

Heat about ½-inch of vegetable oil in a cast iron skillet over medium heat to 350°F. Carefully add 3-4 breaded tomato slices and fry for 3-5 minutes on each side until golden brown and crispy.

Use a slotted spoon to transfer the fried tomatoes to a paper towel lined plate to drain excess oil. Serve hot with a side of the chilled zesty remoulade dip.