Line cupcake tin with liners. Place a vanilla wafer at the bottom of each liner.
Gently beat cream cheese, sugar and vanilla until smooth using an electric mixer. Gradually beat in fat free yogurt, egg whites, lemon juice, lemon zest and flour. Do not over beat. Pour into cupcake liners filling half way.
Bake 25 minutes or until center is almost set. Cool to room temperature. Chill a few hours in the refrigerator.
Top with fresh berries and powdered sugar if desired.