Preheat the oven to 375°.
In a small bowl, mix together the tomatoes, vermouth, basil, shallot, garlic, olive oil, lemon juice, and red pepper and set aside. Take 2 large pieces of foil and spray with cooking spray. Divide the spinach between the two sheets of foil, and place fillets on top of the spinach. Top each fillet with the tomato mixture. Bring up the sides of the foil, fold over, and seal to create a "packet." Seal by turning the edges a small portion at a time, starting at the bottom sides and working to a point. Place sealed packets onto a baking sheet and bake for 20 minutes.
Recipe Courtesy of Eat What You Love: More than 300 Incredible Recipes Low in Sugar, Calories and Fat by Marlene Koch (Running Press 2010)