First, brown the butter. Put the butter in a saucepan over medium heat until melted and then continue to cook while stirring occasionally until butter begins to turn a golden color. Pour it out into a large bowl and set aside. Allow to cool for about 10-15 minutes.
Add the brown sugar to the cooled brown butter and whisk until combined. Add egg yolks and vanilla and whisk until it is smooth and glossy. Add pumpkin puree and whisk until combined.
Sift in the baking soda, salt, pumpkin pie spice and flour and gently mix using a rubber spatula, folding just until combined, and not white streaks of flour remain.
Fold in the chocolate chips and crushed graham crackers (you will add the marshmallows later.
Cover the bowl and refrigerate for 30-45 minutes.
Preheat the oven to 350 degrees and line two large baking sheets with parchment paper.
Scoop up mounds of dough and place them onto the baking sheet, spaced about 2 inches apart from each other and flatten slightly. Top with 2-3 mini marshmallows.
Bake for 9-12 minutes or until the edges are browned and the center looks puffed and slightly cracked.
Allow them to rest on the baking sheet for a few minutes before transferring them to a cooling rack.