Preheat oven to 425°F Rinse fish and pat dry. Place in a 7 x 11 inch baking dish. Combine juice, butter, zest and tarragon in a microwave-safe dish. Cook on high for 1 minute or until butter is melted. Pour over fish. Season with salt and pepper and bake for 10 minutes or until fish reaches 150F on a meat thermometer and flakes easily when tested with a fork.