1.Rinse fillets in cold water, lay on paper towels, sprinkle salt and pepper on both sides.
2.Heat oil in nonstick skillet, (you can use a nonstick grill pan if you like the marks) on medium to high. You want the pan hot just not smoking. Place fillets skin side up. Cook about 4 minutes. Turn with a spatula. It should be nice and charred. While cooking on the other side. Mix the vinegar, lemon juice, water, sugar and garlic powder in a small bowl. Pour over the fillets. Let cook for another 3 to 4 minutes more by moving the pan around a little. The sauce should start to thicken up and the fish should be cooked.
3.Place on top of the steamed spinach. Enjoy this tasty and healthy meal.