Combine sliced strawberries and granulated sugar in a medium saucepan. Cook over medium heat, stirring constantly to break down the strawberries, for about 15 minutes until thickened. Remove from heat and let cool completely.

If you prefer a smooth sauce, blend the mixture with a hand blender or transfer it to a regular blender and blend until smooth. Let the strawberry sauce cool completely.

In a mixing bowl, whip heavy cream, powdered sugar, and vanilla until stiff peaks form. Gently fold in the Cool Whip using a spatula until fully combined.

Add a layer of the cream mixture to the bottom of each serving glass or bowl. Spoon a layer of the cooled strawberry sauce over the cream mixture. Repeat with another layer of cream mixture and another layer of strawberry sauce.

Top with any remaining cream mixture.Sprinkle with crushed graham cracker cookies and garnish with fresh strawberries. Serve immediately or chill until ready to enjoy.