Preheat oven to 400°F. In a small bowl, combine sauce ingredients; set aside. Cut 4 (12-inch square) pieces of aluminum foil. On the center of each sheet of foil, place 1 1/2 cups of spinach. Top with a fish fillet. Drizzle sauce over fish and spinach. Fold in the edges of the foil sheet over the fish; pinch tightly to seal. Place the foil packages onto a baking sheet. Bake for 10 minutes, until the spinach wilts and the fish is cooked through. Cool 5 minutes. Open the packages and fold down the foil to reveal the fish, being careful of the hot steam. Squeeze the lemon or lime juice over the fish before serving. Makes 4 servings.
Approximate Nutrient Analysis per serving (based on 4 servings):
250 calories, 4 g fat, 0.5 g saturated fat, 70 mg cholesterol, 850 mg sodium, 17 g carbohydrate, 2 g fiber, 10 g sugar, 29 g protein