Prep the cod: Pat the fillets dry with paper towels. If the pieces are uneven, fold thin ends under so they cook more evenly.

Season with salt first: Sprinkle both sides with kosher salt and let the fillets rest for 10 minutes on a plate. This light dry brine improves flavor and texture.

Make the lemon-pepper mix: In a small bowl, combine lemon zest (from 1 lemon), 1 to 1.5 teaspoons freshly ground black pepper, 1/2 teaspoon garlic powder, 1/2 teaspoon onion powder, and 1/2 teaspoon paprika. Add 1 to 2 teaspoons olive oil and stir to make a loose paste.

Blot and coat: Gently blot the cod again, then rub the lemon-pepper mixture over all sides. Go easy—cod is delicate. Save the lemon juice for after cooking.

Preheat the air fryer: Heat to 390°F (200°C) for 3 to 5 minutes. Lightly oil the basket or use a perforated parchment liner to reduce sticking.

Air fry: Arrange fillets in a single layer without touching. Cook 7 to 10 minutes, depending on thickness. Thinner pieces may be done at 6 to 7 minutes; thicker pieces may need up to 11 minutes.

Check for doneness: The cod should flake easily and be opaque throughout. An instant-read thermometer should read 130–135°F for moist results (carryover heat finishes the job).

Finish with lemon: Squeeze fresh lemon juice over the hot fish. Add a sprinkle of chopped parsley or dill if you like.

Serve: Pair with steamed green beans, roasted potatoes, a simple salad, or rice. Add extra lemon wedges at the table.