Preheat oven to 425. In a small bowl whisk vinegar, olive oil, soy and garlic together. Add salt and pepper and taste to adjust seasoning. Put fish in a zip lock bag and pour in marinade. Turn to coat evenly. Refrigerate for 1-2 hours. Roast fish in roasting pan, about 10 minutes per inch of thickness, until flaky but still moist. Check with fork if needed. Cut into serving pieces and serve with juices from pan.