Preheat and prep: Heat your oven to 400°F (200°C). Line a sheet pan with parchment or lightly oil it. Pat the salmon dry with paper towels so the topping sticks well.
Season the salmon: Place the salmon on the pan, skin side down if it has skin.
Sprinkle with 1/2 to 3/4 teaspoon kosher salt and a few cracks of black pepper. Drizzle with 1 tablespoon lemon juice.
Mix the topping: In a small bowl, combine the minced garlic, Parmesan, panko, lemon zest, Italian seasoning, red pepper flakes (if using), parsley, and olive oil. Stir until the mixture looks like damp sand that clumps slightly.
Top the salmon: Spoon the mixture evenly over the salmon, pressing lightly so it adheres.
Leave a thin border around the edges so the topping doesn’t spill over as it bakes.
Bake: Cook for 10–14 minutes, depending on thickness. The salmon should flake easily with a fork and look slightly translucent in the center. If your fillet is very thick, add 2–3 more minutes.
Optional broil: For extra color, switch to broil for 1–2 minutes at the end.
Watch closely—parmesan can brown fast.
Finish and serve: Squeeze the remaining lemon juice over the salmon. Shower with a bit more parsley. Serve with lemon wedges and your favorite sides.