Preheat oven to 400°F. Line a rimmed baking sheet with foil and lightly oil it. Pat salmon dry with paper towels.
In a small bowl, whisk olive oil, lemon juice, lemon zest, black pepper, salt, garlic powder, and onion powder until combined.
Place salmon skin-side down on the sheet. Spoon or brush the lemon-pepper mixture evenly over the tops of the fillets.
Bake for 10 to 12 minutes, until the salmon flakes easily with a fork and an instant-read thermometer inserted in the thickest part registers 125°F to 130°F.
While the salmon rests, melt the butter in a small saucepan or microwave-safe bowl. Spoon the melted butter over the hot salmon.
Garnish with chopped parsley and serve immediately with extra lemon wedges if desired.
Notes
Tip: For crispier edges, broil the salmon for 1 to 2 minutes after baking. Air fryer option: cook at 400°F for 8 to 10 minutes. Use skin-on fillets for easiest serving and to help keep the fish moist.