01 - In a shallow bowl, whisk together buttermilk and hot sauce. Add catfish fillets, turning to coat thoroughly. Marinate in the refrigerator for at least 15 minutes.
02 - In another bowl, combine cornmeal, flour, Cajun seasoning, paprika, garlic powder, salt, and black pepper. Mix thoroughly to distribute seasonings evenly.
03 - In a large skillet or deep fryer, heat 1 inch of vegetable oil to 350°F, maintaining consistent temperature throughout the frying process.
04 - Remove catfish from the marinade, allowing excess buttermilk to drip off. Dredge each fillet in the cornmeal mixture, pressing gently to ensure the coating adheres properly.
05 - Fry fillets in batches for 3 to 4 minutes per side until golden brown and cooked through. Avoid overcrowding the pan. Drain on a wire rack or paper towels.
06 - In a bowl, combine mayonnaise, pickles, capers, lemon juice, Dijon mustard, and parsley. Mix well and season with salt and pepper to taste.
07 - Serve the fried catfish hot with tartar sauce on the side. Accompany with traditional sides such as coleslaw, fries, or hush puppies.