In a large mixing bowl, combine 2 cups of heavy whipping cream, 1 cup of powdered sugar, and 2 teaspoons of vanilla extract. Beat on medium speed until soft peaks form.
Add the vanilla pudding mix to the whipped cream and blend gently until fully incorporated.
Gradually add 2 cups of milk while mixing until the mixture is smooth and thickens slightly.
In a 9x13 inch baking dish, lay a single layer of graham crackers on the bottom.
Spread half of the cream filling over the graham crackers, smoothing it out evenly with a spatula.
Add another layer of graham crackers on top of the cream filling, then spread the remaining cream filling over this layer. Finish with a final layer of graham crackers on top.
For the chocolate topping, heat 1 cup of heavy cream in a saucepan over medium heat until it begins to simmer. Remove from heat and add 1 cup of semi-sweet chocolate chips. Stir until the chocolate is completely melted and the mixture is smooth.
Pour the chocolate ganache over the top layer of graham crackers, ensuring an even coat.
Cover the dish with plastic wrap and refrigerate for at least 4 hours, or preferably overnight.
