Cut each fillet lengthwise into 3 strips, each about 1 1/2 inches wide. Thread each strip onto a skewer. Lay them in a shallow bowl.

Combine 1 teaspoon of the Creole seasoning, the salt, cayenne, mustard, and buttermilk in a small mixing bowl and stir to blend. Pour the mixture over the catfish, cover, and refrigerate for 8 hours.

Remove the fish from the refrigerator. Heat the oil to 360°F in a large deep cast-iron skillet.

In a large mixing bowl, combine the flour and the remaining 2 teaspoons Creole seasoning. Dredge 2 to 3 skewers at a time in the flour, shaking off any excess. Fry them in batches until the fish is golden brown and float up to the surface of the oil, about 4 minutes (depending on the thickness of the fillets.) Drain on paper towels. Serve hot with the rémoulade sauce.