Preheat the oven to 400 F. Pour 1 tablespoon of olive oil in a large rectangular baking dish.
Add 4 cod fillets to the baking dish. Top with 1 tablespoon of lemon juice.
Add ¼ cup green olives, ½ a sliced red onion, and 1 package halved cherry tomatoes to the baking dish around the cod.
Sprinkle 1 teaspoon of dried basil, 1 teaspoon of dried dill, 1 teaspoon of dried thyme, ½ teaspoon of salt, and ½ teaspoon of black pepper over the fish and vegetables.
Bake for 10 minutes, or until the cod reaches an internal temperature of 145 F.