Steps
1. In a small bowl, whisk together olive oil, lemon juice, minced garlic, oregano, salt, and pepper.
2. Place the cod fillet in a shallow dish and pour the marinade over it. Let it marinate for at least 15 minutes.
3. Preheat the grill or a grill pan over medium-high heat.
4. Remove the cod from the marinade and place it on the grill. Cook for 3-4 minutes on each side, or until the fish flakes easily with a fork.
5. Serve the grilled cod with lemon slices and a sprinkle of fresh parsley on top.