Pat the cod dry. Use paper towels to remove surface moisture. This helps the marinade stick and promotes light caramelization.

Make the marinade. In a bowl, whisk 2 tablespoons white miso, 1 tablespoon mirin, 1 tablespoon soy sauce, 1 teaspoon honey, 1 teaspoon rice vinegar, 1 teaspoon grated ginger, 1 small minced garlic clove, and 1/2 teaspoon sesame oil until smooth.

Marinate the fish. Coat the cod on all sides with the miso mixture.

Let it sit 15–30 minutes in the fridge. Avoid marinating longer than 45 minutes to keep the texture delicate.

Preheat the air fryer. Set to 380°F (193°C) for 3–5 minutes. Lightly brush or spray the basket with neutral oil to prevent sticking.

Arrange the fillets. Place cod in a single layer, leaving space between pieces.

Spoon a little extra marinade on top for flavor.

Air fry. Cook for 8–10 minutes, depending on thickness. Start checking at 7 minutes. The fish is done when it flakes easily with a fork and reaches an internal temperature of 130–135°F (54–57°C).

Optional caramelization. For a deeper glaze, air fry 1–2 minutes more, watching closely so sugars don’t burn.

Rest briefly. Let the fish sit 2 minutes to settle the juices.

Garnish and serve. Top with green onions and sesame seeds.

Serve with rice, sautéed bok choy, or a cucumber salad, plus lime or lemon wedges.