Cut cleaned catfish to bun size. In a bowl, season catfish with garlic powder, All purpose seasoning, Tony's seasoning and smoked paprika. Mix until the the fish is fully coated.The pour in buttermilk and hot sauce. Allow to marinade for at least 30 minutes.
For the dry batter, combine yellow cornmeal, flour and season with garlic powder, Tony's, lemon pepper, all purpose seasoning and smoked paprika. Mix well.
Preheat oil to 350 degrees. After 30 minutes dredge the soaked fish in the dry batter. Coat well and shake off the excess. Set fish on a wired rack and allow to rest for a few minutes before frying.
Carefully add fish to the hot oil and fry until crispy, about 7-9 minutes. (time will vary depending on the size of the fish) You might have to flip the fish to ensure doneness.
For the sauce
In a small bowl, combine mayo, creole mustard, sweet relish, hot sauce and garlic paste. Season with smoked paprika and garlic powder.
Assemble the sandwich
Cut brioche roll in half. and toast in a medium pan with butter.
Add a layer of sauce, then lettuce, tomatoes, salt, pepper, catfish, more sauce and onions. Add the top bun. Serve with fries or chips and enjoy!