Using a low-fat cheese such as feta makes for a rich but lean topping. The newer feta cheeses with sun-dried tomatoes and basil are especially good.
Preheat oven to 400°F. Line baking sheet with foil. Lightly grease foil.
Combine first 6 ingredients in medium bowl. Season with pepper. Arrange fish on prepared baking sheet. Spread cheese topping over fish.
Bake until fish is just cooked through, approximately 10 minutes.