Puree apple sauce, yogurt, cinnamon, vanilla and sugar in a blender. Add frozen wild blueberries one cup at a time and blend thoroughly. Pour into glasses immediately. Carefully add vanilla yogurt and wild blueberries on top. Garnish with lemon zest as desired.
Approximate nutritional analysis per serving: Calories: 200 Fat: 1.5 g Cholesterol: 5 mg Sodium: 70 mg Carbohydrate: 47 g Protein: 5 g Fiber: 7 g