Start by making the chocolate layer:

1. In a heat-proof bowl, add the chocolate chips and the softened butter.
2. Heat the 3/4 cup heavy cream over medium heat until hot making sure not to bring it to a boil.
3. Pour the heated cream over the chocolate and butter. It will cover it completely. Leave undisturbed for 3-4 minutes and then whisk gently together. You’ll have a very silk chocolate mixture. 
4.  Set aside and allow it to cool while preparing the next layer.

Now make the marshmallow layer:

1. With a stand mixer using the whisk attachment or a hand mixer, beat the heavy cream until stiff peaks form. This usually takes about 2 minutes. Remove to a bowl and set aside. (I refrigerated mine while continuing because it was a hot day).
2. Now add the softened cream cheese to the mixing bowl (no need to wash in between) and the sugar.
3. Mix together for about two minutes, scraping down the sides about halfway. 
4. Add the marshmallow fluff and mix just until combined.
5. Now add 1/2 of the whipped heavy cream to the cream cheese and fluff. Fold in gently making sure not to deflate the heavy cream. Continue adding the rest and gently fold in to the mixture. 

Now you are ready to assemble in your loaf pan:

1. Line a loaf pan with plastic wrap making sure it comes up all four sides. This will make getting the cake out of the pan later much easier. 
2. Line the bottom with graham crackers filling the entire surface. Cut some to fit as needed to fill gaps.
3. Spread a layer of marshmallow cream on the bottom and spread evenly using a small offset spatula. 
4. Pour the cooled chocolate over the marshmallow cream.
5. Add a layer of graham crackers making sure the entire surface is covered.
6. Repeat by spreading the marshmallow cream followed by the chocolate and then another layer of graham crackers. You will end up with a layer of graham crackers. Refrigerate for eight hours and then move to the freezer for a few hours.
7. When you are ready to serve, place a cold plate and turn over so that the cake comes out of the pan.  Remove the plastic wrap and add the final layer of the marshmallow cream that you reserved the day before. Top with mini marshmallows. 
8. Carefully use a kitchen torch to toast the mini marshmallows. Try not to get too close as they will burn easily. 
9. Slice and serve immediately.