In a food processor, process gluten-free graham crackers until finely ground.
In a large bowl, combine flour, finely ground gluten-free graham crackers, salt, baking soda and ground cinnamon. Whisk to combine and set aside.
Cream together granulated sugar, light brown sugar and butter, about 1-2 minutes, until creamy. Add in the eggs and vanilla extract and mix until combined.
Gradually add in the flour mixture to the butter mixture, stirring in between each addition.
Carefully stir in 1 ½ cups of the chocolate chunks, reserving the remaining ½ cup for later.
Chill the dough for at least 1 hour (or overnight) in the fridge.
Preheat the oven to 350º F. Line a baking sheet with parchment paper.
Portion out the dough into 2-3 tablespoons balls. You should be able to make about 24 balls of dough in total.
Place the cookie dough balls on a baking sheet, about 3-inches apart, as the dough will spread. Place remaining cookie dough balls in the freezer until ready to bake.
Bake at 350º F for 9 minutes. Remove from the oven and place a few mini-marshmallows and chocolate chunks on top of each cookie.
Place cookies back into the oven and bake for an additional 3-4 minutes, until cookies are baked through and marshmallows are lightly toasted. Alternatively, you can place the cookies under the broiler for a minute to toast marshmallows.
Allow cookies to cool completely on the baking sheet before removing from the pan.
If you add the marshmallows to the dough before baking, they will dissolve in the oven and create little gooey pockets. That's not necessarily a bad thing, but definitely not what we're going for with these s'mores cookies. Instead, by adding a few marshmallows on top of the cookies just before they finish baking, the marshmallows will lightly melt and brown. There are a few varieties of gluten-free graham crackers on the market, so be sure to check your gluten-free section at the grocery store to find one that is suitable for your needs. You want to measure the graham crackers after they have been finely processed in a food processor. You're looking for the graham crackers to resemble a coarse flour.These cookies spread so I like to only bake about 6 cookies at a time on a baking sheet. This will depend on the size of your baking sheet. I also like to only bake one sheet at a time in the middle rack. However, you can bake 2 sheet pans at the same time, switching the pans halfway through the baking time to ensure even baking. Since I only bake one sheet at a time, I like to freeze the remaining balls of dough until they’re ready to bake.Chilling the dough is a MUST for these cookies since they tend to spread. I always chill my dough in the refrigerator or freezer for at least an hour. If I’m going to prep the dough ahead and bake at a later date, I chill the dough for the hour and then portion it out into balls and freeze the balls for easy baking later.You can use any kind of chocolate instead of the chocolate chunks. I just like that you get more of that s’mores look with the chocolate chunks. You can make these cookies dairy-free by using dairy-free butter and dairy-free chocolate.I always use unsalted butter when I’m baking since different brands have different amounts of salt added in. It’s much easier to measure the amount of salt that you add into the dough if you use unsalted butter. No one wants an overly salty cookie! If for some reason all you have is salted butter, omit the salt required in the recipe.