01 - In a small bowl, combine paprika, onion powder, garlic powder, thyme, oregano, cayenne pepper, black pepper, and salt. Mix thoroughly until evenly distributed.
02 - Pat catfish fillets completely dry with paper towels. Brush both sides of each fillet with melted butter, ensuring even coverage.
03 - Generously coat each fillet with the Cajun spice blend, pressing the seasoning firmly into the fish to ensure adherence.
04 - Heat vegetable oil in a large cast-iron skillet over medium-high heat until just smoking, approximately 2-3 minutes.
05 - Add catfish fillets to the hot skillet, working in batches if necessary to prevent overcrowding. Sear for 3-4 minutes per side until deeply blackened and crispy, and fish flakes easily with a fork.
06 - Transfer catfish to serving plates. Garnish with fresh chopped parsley if desired and serve immediately with lemon wedges on the side.