Start by combining soy sauce, grated ginger, minced garlic, honey, and rice vinegar in a small bowl. Whisk everything together until the mixture is smooth and well blended. The combination creates a sweet, salty, and slightly tangy sauce that perfectly complements the mild cod.
Place the cod fillets in a shallow dish and pour the prepared marinade over them. Turn the fish gently to coat both sides evenly. Allow the fillets to marinate for about 15 minutes so the flavors absorb into the fish.
Warm sesame oil in a non-stick skillet over medium heat until it begins to shimmer. The oil adds a delicious nutty aroma and prevents the fish from sticking. Make sure the pan is hot enough before adding the cod for the best sear.
Remove the fillets from the marinade and place them carefully into the hot skillet. Cook each side for about 3–4 minutes until the fish turns golden and flakes easily with a fork. During the final minute, spoon some of the remaining marinade over the fish to create a glossy glaze.
Once the cod is cooked through, transfer it to a serving plate. Sprinkle chopped green onions and sesame seeds over the top for extra texture and freshness. Serve immediately while the fish is warm and flaky.