In a mixing bowl, combine graham cracker crumbs, melted unsalted butter, and granulated sugar until the mixture resembles wet sand. Transfer this mixture to a 9x13-inch pan and press it down evenly. Chill in the refrigerator for about 15 minutes to set.

While the crust sets, whip the heavy whipping cream with an electric mixer on medium speed until stiff peaks form, about 3 to 5 minutes. Set aside.

In another bowl, combine softened cream cheese, confectioners’ sugar, and a splash of vanilla extract. Beat on medium speed until smooth and creamy, about 2 to 3 minutes.

Gently fold in half of the whipped cream into the cream cheese mixture. Spread this mixture evenly over the chilled graham cracker crust.

Sprinkle mini marshmallows generously over the creamy layer.

In a microwave-safe bowl, combine semi-sweet chocolate chips and a splash of milk. Heat in the microwave at 30-second intervals, stirring until completely melted and smooth. Allow to cool slightly before pouring over the marshmallows.

Spread a layer of marshmallow crème over the ganache.

Dollop the remaining whipped cream over the marshmallow crème layer and smooth out.

(Optional) Sprinkle graham cracker crumbs, mini chocolate chips, and extra mini marshmallows on top.

Cover with plastic wrap and refrigerate for at least 4 hours before serving.