Lightly grease a 9x13 inch baking pan. In a large mixing bowl, combine graham cracker crumbs and granulated sugar. Pour in melted butter and mix until well combined. Press this mixture firmly into the bottom of the prepared pan.

Refrigerate for 30 minutes or bake at 375°F for 8 minutes until lightly golden.

In a medium saucepan, combine the granulated sugar and cornstarch. Gradually add cold water and stir constantly. Bring to a boil, stirring continuously for 1-2 minutes until slightly thickened. Remove from heat, stir in peach Jello until dissolved, then add sliced peaches. Chill for 20 minutes.

In a large mixing bowl, beat the softened cream cheese and powdered sugar together until smooth, about 2-3 minutes. Gradually fold in the whipped topping until fully combined.

Spread the cheesecake filling evenly over the chilled crust. Pour the cooled peach topping over the cheesecake layer and refrigerate for 4-5 hours.

Remove the dessert from the refrigerator and cut into squares. Garnish with extra whipped topping if desired.