Heat the oil to 350 degrees.
While the oil heats, blend the cornmeal, flour, and Cajun seasoning in a shallow dish. Dip the fillets in buttermilk, then dredge in the cornmeal blend. Move the dredged fillets from the cornmeal to a wire rack to rest while you dredge the remaining fillets. The resting period allows the crust to set on the fillet, helping it to stay on the fish during the cooking process.
Dip the catfish fillets into the buttermilk, then into the seasoned corn meal mixture.
Deep fry the catfish in batches, taking care not to overcrowd the pan. Fry the fish for 5 to 7 minutes, or until the cornmeal coating is golden brown and the fish is cooked through and flaky.
Fry the fish in batches in 350 degree oil.
Transfer each batch to a wire rack while the remaining catfish cooks.
Drain the crispy catfish on a wire rack while you continue frying the next batch.
Pour 2 cups of Buffalo wing sauce into a shallow dish. Dip the fried catfish into the sauce, letting the excess drip back into the dish before transferring the fillets to a bun. Top the dipped catfish with a scoop of creamy coleslaw and a sprinkle of blue cheese crumbles. Serve with fries or onion rings.
Dip the fried catfish in your favorite Buffalo sauce.