Preheat your oven to 350°F (175°C). Line a baking sheet with parchment paper.
In a medium bowl, whisk together the flour, baking soda, and salt. Set aside.
In a large mixing bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy, about 2-3 minutes.
Beat in the egg and vanilla extract until well combined.
Gradually mix in the dry ingredients, stirring until just combined. Be careful not to overmix.
Fold in the chocolate chips, mini marshmallows, and crushed graham crackers.
Scoop out tablespoon-sized dough balls and place them onto the prepared baking sheet, spacing them about 2 inches apart.
Bake in the preheated oven for 10-12 minutes, or until the edges are lightly golden, and the centers still look slightly soft.
Remove from the oven and let cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.
Notes
Serve the cookies stacked on a plate, drizzled with a little melted chocolate, and garnished with additional mini marshmallows on top for that ultimate S’mores feel!