In a large bowl, prepare the batter by combining the buttermilk, egg, mustard, and hot sauce.

Place the catfish filets in the buttermilk mixture and marinate for 30 minutes.

In a shallow dish, mix together the cornmeal, salt, paprika, cayenne pepper, dill, garlic powder, and black pepper.

Heat the oil in a large skillet over medium-high heat. Remove each filet from the marinade and shake off any excess. Coat both sides with the cornmeal mixture. Shake off excess cornmeal and fry for 3 minutes on each side.