Preheat the air fryer: Set it to 390°F (200°C) for about 3–5 minutes. Preheating helps the crust brown nicely.

Prep the basket: Lightly spray the basket or line it with a perforated parchment sheet. Avoid solid foil sheets that block airflow.

Pat the salmon dry: Use paper towels to remove surface moisture. Dry salmon browns better and holds the topping.

Season the fillets: Sprinkle both sides with salt and pepper. If skin-on, season the flesh side a bit more generously.

Mix the topping: In a small bowl, combine parmesan, minced garlic, mayo, olive oil, lemon zest, lemon juice, parsley, and panko (if using). Add a pinch of smoked paprika or chili flakes if you like heat. The mixture should be spreadable, not runny.

Spread the crust: Place salmon in the basket skin-side down if using skin. Spoon the mixture over the top and spread into an even layer. Press gently so it adheres.

Air fry: Cook for 7–10 minutes, depending on thickness and your preferred doneness. Thicker fillets (1.25 inches) may need up to 11–12 minutes.

Check doneness: The salmon should flake easily with a fork, and the crust should be golden. An instant-read thermometer should read 125–130°F (52–54°C) for medium, or up to 140°F (60°C) for well-done.

Rest briefly: Let it sit 2 minutes to finish cooking gently and reabsorb juices.

Serve: Add a squeeze of fresh lemon and extra parsley. Pair with a crisp side salad, garlic green beans, or buttered rice.