Crush graham cracker crumbs. Can place them in a gallon size ziplock bag and use a rolling pin to crush, or food processor. Melt the butter and mix together until evenly moistened.
Coat an 8x8 square baking pan with cooking spray and preheat your oven to 350 degrees. Press graham cracker crumbs evenly in the bottom of the pan.
In an electric mixer blend cream cheese, sugar, and vanilla until smooth. Gradually beat in the fat free yogurt, egg whites, lemon juice and flour just until blended. Do not over-mix. Pour over the graham cracker crust.
Stir your jam until smooth. Drop by small spoonfuls over the cheesecake surface. Using a knife, swirl the jam throughout the cheesecake to create a marble effect.
Bake 25 to 30 minutes or until the center is almost set. Don't let the edges get too brown. Cool at room temperature and chill a few hours in the refrigerator.
Melt your chocolate chips in microwave and barely drizzle the top with the melted chocolate.