Lightly grease the sides of an 8x8" square pan. Place a sheet of parchment paper in it that's long enough to hang over the edge and clip it with binder clips.

Place the golden grahams in a large bowl and use your hands to crush some of them so they’re not all quite as big and have some dimension.

Place butter into a medium-size saucepan and heat it over medium-low heat. Stir occasionally (if the butter is cold, cut it into cubes first).

As the butter begins to bubble and foam, stir continuously. You’ll need to scrape the solids off the bottom of the pan. The milk solids will start to settle and darken.

Remove it from the heat and continue stirring for about another minute until the butter darkens into an amber color.

Add the marshmallows to the bowl and stir over low-medium heat until they’re completely melted.

Pour the melted mixture over the golden grahams and fold it all in quickly until it’s mostly combined.

Add the chocolate and marshmallow fluff and fold them in until they’re evenly distributed - this is kind of difficult, just do your best and then press it into the prepared pan.

Refrigerate for a few hours to set (it sets quickly, like 20 minutes but it tastes so much better after a few hours)