01 - Pat catfish fillets dry with paper towels and brush both sides generously with olive oil.
02 - In a small mixing bowl, combine paprika, smoked paprika, garlic powder, onion powder, dried thyme, dried oregano, cayenne pepper, black pepper, and salt. Mix thoroughly until evenly distributed.
03 - Sprinkle the blackening spice mixture evenly over both sides of each catfish fillet, pressing gently to ensure the seasoning adheres securely.
04 - Place a cast iron skillet over medium-high heat and allow it to heat for 2-3 minutes until almost smoking.
05 - Add the seasoned catfish fillets to the dry skillet without overcrowding. Cook for 3-4 minutes per side until the fish becomes opaque and flakes easily with a fork. Work in batches if necessary to avoid crowding.
06 - While the fish cooks, melt unsalted butter in a small saucepan over low heat. Stir in lemon zest, lemon juice, and finely chopped parsley. Remove from heat immediately.
07 - Transfer the blackened catfish fillets to serving plates. Drizzle generously with the warm lemon butter sauce and garnish with additional fresh parsley if desired. Serve immediately.