Heat oven to 375. Line two baking sheets with parchment paper and set aside.

In a medium bowl, combine the flour, graham cracker crumbs, baking soda and salt. Stir well to mix.

In a separate large bowl, beat the butter and both sugars together until light and fluffy, using either a stand mixer or hand mixer. (You can do it with a whisk too, it just takes a little longer.) Beat the eggs and vanilla into the butter mixture.

Add the dry ingredients to the wet ingredients and stir until just mixed.

Fold in the chocolate chips, ¾ cup of the marshmallows and half of the chopped chocolate bars.

Roll the batter into balls, about 1 inch in diameter, and place on the baking sheets. (It helps to lightly wet your hands with water so the cookie batter doesn’t stick to you.) Be sure to leave about 2 inches between the cookies.

Bake at 375 for 8 minutes.

Remove the cookies from the oven and, working quickly, add some of the remaining mini marshmallows and chopped chocolate pieces to the tops of the cookies, pressing in slightly so they stick into the still not fully baked cookies.

Return the baking sheets to the oven and bake the cookies for an additional 2-3 minutes, until the cookies are set and the marshmallows are puffed.

Remove and let cool for 5-10 minutes on the baking sheets before transferring to a piece of wax paper to cool completely. (They are very soft out of the oven and need to sit to finish setting up, so they won’t fall completely apart when you move them.)

Repeat with remaining batter and bake the last batch of cookies.

Store cooled cookies in a ziptop bag or a plastic container for up to a week. (You can separate layers with wax paper so they don’t stick to each other.)