Prepare Strawberry topping: Puree strawberries in a blender or food processor to create mostly strawberry juice. Press pureed strawberries through a fine mesh strainer in to a small saucepan. In a small bowl, mix together 3 tablespoons sugar and cornstarch. Stir into the strawberry juice in the saucepan. Bring to a boil over medium heat, stirring constantly, until sauce thickens and is clear. Cool to room temperature, then refrigerate until chilled, at least 1 hour.
(Optional: Crisp up the fillo shells in a preheated 350° on a baking sheet for 3 - 5 minutes, until golden browned and crispy. Remove to a wire rack to cool completely before filling.)
In a small mixing bowl, beat together cream cheese, sour cream, 2 tablespoons sugar, lime juice, and 1 teaspoon lime zest until smooth.
Fill each shell with the cream cheese mixture. Top each with one to two teaspoons of strawberry topping. Garnish with a strawberry on a skewer.