Combine the salted butter and sugars in a large mixing bowl. Using an electric hand mixer, cream the butter and sugars together for about 2 minutes or until homogenous.
Add the egg and vanilla. Whisk again until the egg is fully incorporated. Gently whisk the graham crackers, flour, baking powder, and baking soda into the wet ingredients until no clumps of dry ingredients remain.
Fill a mini muffin tin with your cookie dough and bake for 11 minutes. Cut your marshmallows in half.
Remove the pan from the oven and immediately use the handle of a spoon to create a small indent in the center of each cookie cup. Fill the indents with chocolate chips and top with a marshmallow half with the sticky side facing down.
Set your oven to broil on high and bake the cookies for an additional 2 minutes or until the marshmallows are golden brown. Watch them closely as marshmallows burn quickly. Enjoy!
Notes
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