Preheat your oven to 400°F (200°C). Place the cod fillets on a clean plate and pat dry with paper towels.
In a small mixing bowl, whisk together the olive oil, lemon juice, oregano, salt, and pepper until well combined.
2 fillets cod fillets
Brush the marinade evenly over both sides of each cod fillet using a basting brush or spoon, ensuring all surfaces are coated.
2 fillets cod fillets
Arrange the seasoned fillets in a baking dish, skin-side down if applicable, and drizzle any remaining marinade over the top.
2 fillets cod fillets
Bake in the preheated oven for 12-15 minutes, or until the fish is opaque and flakes easily with a fork. Watch for the edges to turn a light golden color and the center to look moist and flaky.
2 fillets cod fillets
Remove the baking dish from the oven, transfer the fish to plates, and optionally garnish with lemon wedges or fresh herbs before serving.
2 fillets cod fillets