Pat the fish dry with paper towels and season lightly with the Cajun seasoning on both sides.
Mix together the melted butter, lime juice, garlic, cilantro, and a little bit more Cajun seasoning.
Preheat the Blackstone griddle to medium heat for several minutes. Once hot add half of the seasoned butter on the griddle and place the catfish fillets over top of the butter.
Cook the catfish about 3 minutes, flip the fish, and pour the remaining butter mixture over top. Let the fish cook about another 3 minutes.