Line an 8″-x-8″ pan with parchment paper or butter it generously.⁣

Melt butter in a large pot over medium-low heat. Add the bag (6 cups) of marshmallows. Stir until the marshmallows are melted. ⁣

Remove the pan from the heat. Add the graham cereal. Stir gently to combine. Add the additional 2 cups marshmallows and chopped chocolate. Stir quickly to combine. (If you stir for too long, the chocolate will melt. The bars still taste great!)⁣

Press the mixture gently into the prepared pan with a piece of greased parchment paper or your hands. If using your hands, grease them lightly or the cereal mixture will stick.⁣

Let the bars cool. You can do this at room temperature or in the refrigerator. Cut into bars. Enjoy!

Store the bars covered at room temperature for up to four days. For firmer bars, store covered in the refrigerator.