01 - Preheat oven to 400°F. Line a baking sheet with parchment paper or lightly grease with cooking spray.
02 - Pat salmon fillets dry with paper towels to remove excess moisture. Place fillets skin-side down on the prepared baking sheet.
03 - In a small mixing bowl, combine Cajun seasoning, paprika, garlic powder, onion powder, dried thyme, dried oregano, and cayenne pepper. Stir until thoroughly blended.
04 - Drizzle olive oil evenly over each salmon fillet. Gently rub the oil into the fish to ensure even coverage.
05 - Sprinkle the Cajun seasoning mixture generously over each fillet, pressing gently to adhere. Season with additional salt and black pepper as desired.
06 - Place a lemon slice on top of each seasoned salmon fillet to infuse citrus flavor during baking.
07 - Bake for 12–15 minutes until salmon flakes easily with a fork and reaches an internal temperature of 145°F. The fish should appear opaque throughout.
08 - Remove from oven and immediately garnish with chopped fresh parsley. Serve hot with your choice of sides.