In a saucepan, combine the chopped rhubarb, granulated sugar, and water. Cook over medium heat until the rhubarb softens, about 10 minutes. Stir occasionally and allow the mixture to bubble gently.

Once softened, mix the cornstarch with a little water to create a slurry. Add to the rhubarb mixture, stirring constantly until thickened and glossy. Remove from heat and let it cool completely.

In a bowl, combine graham cracker crumbs with melted butter until evenly moistened.

Press half of the crumb mixture into the bottom of a 9x13 inch baking dish to form a firm crust.

In a separate mixing bowl, blend softened cream cheese and powdered sugar until smooth. Fold in the whipped topping gently to keep it light and airy.

Spread half of the cream cheese mixture over the crust, followed by half of the cooled rhubarb mixture. Repeat with the remaining cream cheese mixture and top with the rest of the rhubarb.

Sprinkle the remaining graham cracker crumbs on top.

Chill dessert in the refrigerator for at least 4 hours before serving.

Garnish with fresh mint leaves and sliced strawberries before serving.