Let egg whites stand in a large mixing bowl at room temperature for 30 minutes. Add the vanilla, cream of tartar, and salt to egg whites. Beat with an electric mixer on medium speed until soft peaks form (tips curl). Add sugar, a tablespoon at a time, beating about 7 minutes on high speed or until stiff peaks form (tips stand straight) and sugar is almost dissolved. Fold in very finely chopped almonds.

Cover a large baking sheet with clean plain brown paper or parchment paper. Draw six 4-inch-long heart shapes on paper. Using a pastry bag fitted with a large star tip, pipe the meringue onto the hearts on the paper, building the sides up to form shells. (Or, use the back of a spoon to spread the meringue over the hearts, building up the sides.)

Bake in a 300 degree F oven for 35 minutes. Turn off oven. Let shells dry in oven, with the door closed, for at least 1 hour. Remove from paper.

Meanwhile, thaw berries, if frozen. Do not drain. Place half of the berries in a blender container or food processor bowl. Cover and blend or process until berries are smooth. Press berries through a fine-mesh sieve; discard seeds. Repeat with remaining berries. (Should have about 1-1/4 cups.)

In a medium saucepan stir together sieved berries, preserves, and cornstarch. Cook and stir over medium heat until thickened and bubbly. Cook and stir for 2 minutes more. Remove from heat. Cool to room temperature.

To serve, scoop sorbet or frozen yogurt into meringue hearts. Spoon berry sauce atop. Sprinkle with sliced almonds. If desired, garnish with additional fresh raspberries. Makes 6 servings.

Bake the meringue hearts 1 day ahead. Store in an airtight container.