Preheat your oven to 375 and line an 8x8 pan with parchment paper.
Crush the sleeve of graham crackers in a baggie or shallow container, then mix with 1/4 cup of sugar.
Reserve a little bit of the mixture to be sprinkled on top later, then stir in the melted butter and pour into your pan. Press down to form a crust.
Bake the crust for 15 minutes to get it nice and toasty.
In a small sauce pan, add the milk chocolate chips, vanilla extract, and 1/2 can of sweetened condensed milk. Stir consistently until melted.
Pour the chocolate mixture over the crust to form the chocolate layer.
In another sauce pan (or the same one...I'm not judging), repeat the cooking process with the white chocolate chips, marshmallow fluff, and sweetened condensed milk. Pour the resulting ooey-gooey-ness over the chocolate layer to form the marshmallow layer.
Sprinkle your leftover crushed graham crackers on top to make it look nice and pretty.
And now, for the hardest part: put that delicious mixture of s'mores goodness into the fridge to let it set. Give it at least a few hours, but preferable overnight.
Once you've survived the night of waiting, use that handy parchment paper to lift the s'mores fudge out of the pan. Slice it up and enjoy!