Cook fish for 4 minutes on each side, until cooked through.
Remove fish from skillet and cover loosely with foil to keep warm.
Add butter to pan the fish cooked in. Brown the butter over med heat for 2-3 minutes, then stir in the balsamic vinegar and simmer for 1-2 minutes to reduce by half.
Pour the brown butter sauce over the fish.
Nutrition Info Per Serving: Calories 410.5 Total Fat 20.1 g Saturated Fat 8.0 g Polyunsaturated Fat 2.3 g Monounsaturated Fat 8.8 g Cholesterol 121.0 mg Sodium 162.2 mg Potassium 669.5 mg Total Carbohydrate 13.0 g Dietary Fiber 0.5 g Sugars 0.0 g Protein 46.0 g