Preheat the oven to 350° then lightly spray a 24-count mini muffin pan with cooking spray.
In a small bowl, whisk the graham cracker crumbs, flour, baking soda and salt then set it aside.
In a medium bowl using a hand mixer, cream the softened butter and both sugars together then fold in the egg and vanilla until everything is thoroughly combined.
Add the ‘dry’ ingredients to the ‘wet’ ingredients stirring until they’re combined.
Using a 1″ scooper form 24 balls dropping them into the prepared mini muffin tin then gently press down on the ball forming the cup using a teaspoon size measuring spoon.
Bake 8-9 minutes until golden then remove from the oven.
NOTE: cups puff up in the baking process. While they're still warm, use the same teaspoon measuring spoon and press down to reform the cup. add 4 mini marshmallows to each cup, gently pressing to nestle them in.
Transfer the muffin tin to the broiler for about 1 minute watching very carefully so they don’t burn. OPTIONAL: If you have a brûlée torch you can use this instead.
Remove the muffin tin from the oven and press a piece of Hershey’s chocolate into the top of each cookie cup. Cool to room temp and enjoy.