Place a 14-inch skillet or sauté pan on the stovetop and bring to medium heat. Add olive oil.
Sauté onions and garlic until translucent, about 5 minutes. Add oregano, thyme, green olives, lemon zest, lemon juice, diced tomato, and capers. Continue to cook for an additional 10 minutes.
Place four equal portions of cod in a 9 x 12-inch baking dish. Season the cod with kosher salt and cracked pepper to taste. Spoon over hot tomato and olive-caper sauce—bake for about 15 minutes.
Garnish the baked cod dish with chopped parsley and slices of fresh lemon. Serve over saffron rice or rice of your choice.
Notes
Do not overcook the fish. Use your judgment when you place your fork into the fish. It should flake apart easily. It may take a little more time if the fish is thicker.