½ cup fresh raspberries, strawberries, and/or blueberries
Coat a 9-inch fluted tart pan with a removable bottom with cooking spray; set aside. To prepare the crust: In a small bowl, combine the cookie crumbs and melted butter. Press the crumb mixture evenly over the bottom of the prepared tart pan. Set aside.
To prepare the Raspberry Filling: Place thawed raspberries in a food processor or blender. Cover and process or blend until smooth. Strain through a fine-mesh sieve, pressing with a wooden spoon or rubber spatula to extract as much of the mixture as possible (about 1 cup). Discard the solids.
In a large bowl, combine the warm water and dried egg whites; stir about 2 minutes or until egg whites dissolve. Beat with an electric mixer on medium to high speed for 2 to 3 minutes or until soft peaks form (tips curl). Gradually add sugar, 1 tablespoon at a time, beating about 3 minutes more or until stiff and glossy peaks form (tips stand straight).
Add about one-fourth of the egg white mixture to the raspberry mixture, whisking until smooth. Add the lightened raspberry mixture to the egg white mixture in the bowl. Using whisk, gently fold together until no white streaks remain. Pour filling into crust; smooth the top. Cover with plastic wrap or foil and freeze for 8 to 24 hours.
To serve, let stand at room temperature for 10 minutes. Carefully remove the sides of the tart pan. Cut into wedges. Garnish with fresh berries.
Tips: For the cookie crumbs, finely crush sugar-free chocolate cookies, such as Murray® Sugar Free Chocolate Cookies in 100-calorie packets. If you are using the packets, you'll find that six packets make about 1 cup crumbs.
Look for dried egg whites in the baking aisle of your supermarket or at a specialty food store.
We do not recommend using a sugar substitute for this recipe.