Prep the oven and pan: Preheat your oven to 400°F (200°C). Line a rimmed baking sheet with foil or parchment for easy cleanup.
Lightly brush with olive oil to prevent sticking.
Pat the salmon dry: Use paper towels to remove surface moisture. This helps the butter mixture cling and encourages better browning. Place the salmon on the baking sheet, skin-side down if it has skin.
Make the garlic butter: In a small bowl, mix melted butter, garlic, lemon juice, lemon zest, parsley, paprika, salt, pepper, and red pepper flakes if using.
Stir until combined.
Season the fish: Lightly sprinkle the salmon with a pinch of salt. Spoon the garlic butter over the top, spreading it evenly. Leave a thin margin around the edges so it doesn’t all slide off during baking.
Add the Parmesan: Sprinkle the grated Parmesan evenly over the salmon.
Press it gently so it adheres to the buttered surface.
Bake: Place the pan on the middle rack. Bake 10–14 minutes, depending on thickness. A thick center-cut fillet will take closer to 14 minutes.
The salmon is done when it flakes easily and the center is slightly translucent, about 125–130°F (52–54°C) for medium.
Optional broil for color: If you want extra browning, switch to broil for 1–2 minutes. Watch closely so the cheese doesn’t burn.
Rest and garnish: Let the salmon rest 3 minutes. Finish with a squeeze of lemon and a sprinkle of fresh parsley.
Serve with lemon wedges.