Preheat the air fryer: Set to 390°F (200°C). Preheating helps the salmon cook evenly and form a light crust.
Pat the salmon dry: Use paper towels to remove excess moisture. Dry fish sears better and won’t steam.
Mix the marinade: In a small bowl, combine olive oil, lemon zest, lemon juice, garlic, Dijon (if using), honey (if using), salt, pepper, paprika, and red pepper flakes. Stir until glossy and emulsified.
Coat the fillets: Brush or spoon the mixture over the top and sides of the salmon. If the skin is on, leave the skin side mostly plain so it crisps.
Prep the basket: Lightly spray the basket with olive oil spray or line with perforated parchment made for air fryers. This reduces sticking.
Arrange the salmon: Place fillets in the basket in a single layer, skin side down if using skin-on. Leave a little space between pieces for airflow.
Air fry: Cook for 7–10 minutes, depending on thickness. Start checking at 7 minutes. The salmon is done when it flakes easily with a fork and reaches 125–130°F in the thickest part for medium, or up to 145°F if you prefer well-done.
Rest briefly: Let the salmon sit for 2 minutes after cooking. Residual heat finishes the job and keeps it juicy.
Garnish and serve: Sprinkle with chopped parsley or dill and serve with lemon wedges. It’s great with roasted asparagus, a simple arugula salad, quinoa, or garlic green beans.