Preheat the oven to 325.
Next, prepare the cheesecake crust. Crumble 2 packages of graham crackers. I did this by pulsing the graham crackers in my blender. 10 or so 2-second pulses made quick work of the graham cracker crumbs.
In a medium bowl, combine melted butter, sugars, and cinnamon. When this is well blended, stir in the graham cracker crumbs and mix until the crumbs are evenly moist.
Press crust mixture into a 9-inch springform pan, making the crust smooth across the bottom and slightly up the sides. Sprinkle with a thick layer of mini marshmallows and top with a drizzle of hot fudge sauce.
Using a stand mixer (if possible, this would work with any mixer or even a whisk but would be much more difficult), blend cream cheese, milk, vanilla, and eggs until just combined. (You never want to over-blend a cheesecake as this will cause it to crack as it cools.)
Pour ½ of batter over the fudgey marshmallows and crust. Top with more marshmallows and more hot fudge sauce and then spread the rest of the batter over top.
Bake the cheesecake for 45 minutes. It is finished even though the center is still soft and jiggly.
Remove the cheesecake from the oven and top with full-size marshmallows. Pack them in so that none of the cheesecake shows through. Return cheesecake to the oven for 5-10 minutes to toast the marshmallows. Watch carefully as marshmallows go from toasted to burnt in about four seconds.
Cool the cheesecake in the refrigerator for 4 hours or overnight.
To serve, remove the sides of the springform pan. Crumble additional graham crackers over the top of the toasted marshmallows, if desired. Stick chocolate bar segments in the marshmallows.
Drizzle entire cheesecake with additional hot fudge sauce.
Serve cold.