01 - Set your air fryer to 350°F (180°C) and allow it to preheat while you prepare the ingredients.
02 - In a mixing bowl, combine the sliced red bell pepper, zucchini, red onion, halved cherry tomatoes, Kalamata olives, sliced garlic, chopped parsley, and dried oregano. Drizzle with half of the olive oil, the lemon juice, salt, and pepper. Toss until everything is evenly coated.
03 - Cut 4 large sheets of parchment paper, approximately 12x16 inches each, and lay them flat on your work surface.
04 - Place one cod fillet in the center of each parchment sheet. Season generously with salt and pepper on both sides.
05 - Divide the seasoned vegetable mixture evenly among the four fillets, mounding it on top. Arrange 2–3 lemon slices over each portion and drizzle with the remaining olive oil.
06 - Fold the parchment paper over each fillet and crimp the edges tightly together to form sealed packets (en papillote), ensuring no steam can escape during cooking.
07 - Place the parchment packets in the air fryer basket, working in batches if needed to avoid overcrowding. Arrange them in a single layer.
08 - Cook for 13–15 minutes until the cod is opaque throughout and flakes easily when tested with a fork.
09 - Carefully open the parchment packets, watching for hot steam. Serve directly in the parchment for a rustic presentation, or transfer to individual plates.