S'Mores Cake

Put butter in a microwave-safe container and microwave on high power for 30 seconds or until completely melted. Or, melt the butter in a pan.
Put the graham crackers in a sealed plastic bag. Use a rolling pin to finely crush the crackers into crumbs (you should have about 1 1/2 cups). Pour the crumbs into the baking pan.
Add the sugar and melted butter. Stir with a wooden spoon until thoroughly mixed. Remove a third of the cracker mixture. Set aside for later.
Gently spread the rest of the cracker mixture evenly in the baking pan. Put the baking pan in the freezer for ten minutes.
Remove the lid from the fudge topping jar. Place the jar in a microwave oven and cook on high for 40 seconds or until soupy and thin enough to pour.
Pour over the chilled cracker crust.
Pour the milk into a large bowl and add the pudding mix. Beat with an electric mixer on medium speed for 2 minutes or until foamy. Use a rubber scraper or spatula to stir in half of the whipped cream topping.
Pour the beaten and stirred pudding mix on top of the marshmallows. Use the rubber scraper to spread the pudding mix evenly across the crumb layer set in the baking pan.
Sprinkle the rest of the marshmallows, the saved cracker mixture, and the chocolate pieces on top of the pudding mix.
Cover with foil, and put it into the refrigerator for 3 to 4 hours before serving, or freeze until firm.
Decorate with more marshmallows and some chocolate curls.