Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or lightly grease it with cooking spray.
Pat the salmon fillets dry with paper towels and season both sides with Cajun seasoning, salt, and pepper.
In a large oven-safe skillet, heat the olive oil over medium-high heat. Once hot, add the salmon fillets skin-side down and sear for about 3-4 minutes until the skin is crispy.
Carefully flip the salmon fillets over and add the butter, honey, and lemon juice to the skillet. Allow the butter to melt and baste the salmon with the honey butter sauce.
Transfer the skillet to the preheated oven and bake for an additional 5-7 minutes, or until the salmon is cooked through and flakes easily with a fork.
Remove from the oven and drizzle any remaining honey butter sauce over the salmon. Garnish with chopped parsley if desired.