What kids, regardless of their "real" age, don't love peanut butter, marshmallow cream, and chocolate all wrapped up in one? On a recipe development grocery run, I spied the fluffy stuff staring at me brazenly from a shelf, right next to the peanut butter. My neighbor Lucie had recently turned me on to the wonders of chocolate graham crackers, so that became the crust that cradles this decadent tart filled with a mousse-like blend of cream cheese, marshmallow cream, and peanut butter.
It can be fully assembled ahead of time and chilled overnight. However, save whipping the cream until just a few hours before service. This is heartbreakingly good and beautiful to look at! Its richness and pumpkin-colored hue are perfect for fall and winter indulgences.
Combine all of the ingredients in a medium-sized bowl. Whisk to combine, or blend with a handheld mixer until very fluffy and smooth.
Preheat the oven to 375 degrees.
Combine the butter and cracker crumbs in a small bowl, using your hands, until thoroughly mixed. Press the crust evenly into the bottom of a 9-by-1-inch round tart pan with removable bottom, pressing the crumbs into the edges. (It's OK if it looks a little rough and rustic.)
Fill with parchment paper and beans or pie weights, and blind bake for 25 minutes. Remove the parchment paper and pie weights and continue baking until the crust starts to dry out and crisp, about 20 more minutes. Remove from the oven and set aside to cool. Refrigerate to chill until completely cooled.
Remove from the refrigerator and add the filling to the crust. Smooth with a spatula to the edges of the tart. Refrigerate for several hours, or overnight if desired. If serving within the next few hours, proceed to whip the cream, sugar, and vanilla extract together in a cold medium-sized bowl until firm peaks have formed.
All at once, place the whipped cream on top of the tart. Spread with a spatula to level it out, leaving ½-inch visible border of the peanut butter filling. Sprinkle chocolate chunks or chips over the whipped cream. Chill for at least 1 hour and up to 3 hours before serving.