Preheat your oven to 350°F (175°C). In a mixing bowl, combine crushed graham crackers with melted butter and sugar until well blended. Firmly press into the bottom of a 9-inch springform pan and bake for 10 minutes. Cool completely on a wire rack.

Lower the oven temperature to 325°F (163°C). In a large bowl, beat cream cheese until smooth. Gradually mix in sugar, raspberry puree, vanilla extract, and cornstarch. Add eggs one at a time. Incorporate pink food coloring if desired.

Pour cheesecake filling over the cool crust. Wrap the bottom of the pan with foil and place in a water bath. Bake for 55-65 minutes, or until edges are set with a slight jiggle in the center. Cool in the oven with the door ajar for 1 hour.

In a saucepan over medium heat, combine raspberry puree, sugar, and cornstarch, stirring until thickened, approximately 5-7 minutes. Cool before drizzling over the cheesecake.

Refrigerate cheesecake for at least 6 hours or overnight for best results. Serve with whipped cream and whole raspberries.