In a large bowl, stir together the mustard, hot sauce and egg white. Add the fish and toss to coat well. Cover and marinate in the refrigerator for 1 hour.
Pour the oil into a Dutch oven, filling it no more than one-third full. Heat the oil over medium heat until it reaches 350 degrees F on a deep-fry thermometer. Line a plate with paper towels and set by the cooktop. In a shallow dish, combine the cornmeal and flour and season with salt and pepper.
Remove the fish from the marinade and sprinkle with salt and pepper. Dredge the fish in the cornmeal mixture to coat both sides and shake off the excess. Carefully add the fish to the oil, a few pieces at a time. Cook until golden brown and crispy, 2 minutes total. Remove with a slotted spoon to the prepared plate.
Serve with Country Remoulade and Beer Batter Hushpuppies.
In a bowl, combine the mayonnaise, chives, lemon juice, mustard, hot sauce, green onions, celery and garlic. Season with salt and pepper.
Cover and refrigerate for 1 hour to blend the flavors. Taste and adjust for seasoning with salt and pepper. Store in an airtight container in the refrigerator for up to 3 days. Serve chilled.
In a large cast-iron Dutch oven, heat the oil over high heat until it reaches 375 degrees F on a deep-fry thermometer.
To make the batter, in a large bowl, whisk together the cornmeal, baking powder, cayenne pepper and 1 teaspoon salt. In a second bowl or large liquid measuring cup, combine the beer, eggs and onions. Add some salt and pepper and whisk until smooth. Stir the wet ingredients into the dry ingredients, using as few strokes as possible. (The mixture should resemble wet sand; add more beer, if needed.)
Line a plate with paper towels and set by the cooktop. To fry the hushpuppies, scoop up the batter using a medium ice cream scoop and drop it into the hot oil without crowding. Fry, stirring occasionally with a slotted spoon, until golden brown, 3 to 5 minutes. Remove with a slotted spoon to the prepared plate. Adjust the heat to maintain the proper temperature and repeat with the remaining batter. Serve immediately.