01 - Combine crushed graham crackers with melted butter in a mixing bowl until mixture resembles wet sand. Firmly press the mixture into the bottom of a 9x9 inch baking dish to create an even base layer.
02 - In a separate bowl, beat cold heavy cream with powdered sugar and vanilla extract using an electric mixer or whisk until stiff peaks form.
03 - In another bowl, whisk together the instant vanilla pudding mix and cold whole milk for 2 minutes. Allow mixture to stand for 5 minutes to thicken.
04 - Spread half of the whipped cream evenly over the prepared cookie base.
05 - Spoon the vanilla pudding over the whipped cream layer and spread into an even layer using a spatula.
06 - Cover the pudding layer with the remaining whipped cream, smoothing the surface gently with a spatula.
07 - Sprinkle chocolate shavings or dust with cocoa powder on top, if desired. Cover the dish with plastic wrap and refrigerate for at least 2 hours, or overnight, to allow the layers to set.
08 - Cut into portions and serve chilled.