Preheat the oven to 350 degrees.
Add 11-12 graham cracker sheets to a food processor and blend until you have fine crumbs (you can also place the graham crackers in a gallon bag and crush using a rolling pin).
Pour the graham cracker crumbs, melted butter and granulated sugar into a medium mixing bowl and mix until well combined.
Use your fingers or the back of a measuring cup to press the graham cracker mixture evenly throughout a 9-inch pie plate. I recommend using a deep dish pie plate - if you aren't using one, you will have some extra crust mixture and chocolate cream mixture.
Bake the crust for 6 minutes, then remove it from the oven and add 2 cups of mini marshmallows evenly throughout the bottom of the pan (lightly press them down).
Return the crust + mini marshmallows to the oven for 3-4 minutes or until the marshmallows just begin to brown and melt together.
Remove it from the oven and allow it to cool to room temperature before adding the chocolate cream layer.