Ingredient:

• 2 tablespoons olive oil
• 1 onion, thinly sliced
• 2 cloves garlic, minced
• 1 (14.5 ounce) can diced tomatoes
• ½ cup black olives, pitted and sliced
• 1 tablespoon chopped fresh parsley
• ½ cup dry white wine
• 1 pound cod fillets