Preheat oven to 350℉
Line a 9 x 13 baking pan with parchment paper or use nonstick cooking spray or butter to grease pan.
In a large microwaveable mixing bowl, combine butter and 1 cup of chocolate chips, and melt in short increments in microwave. Allow to cool slightly
Whisk in the vanilla and eggs, one at a time
Add the sugar, flour, baking soda and cinnamon, and stir until combined
Stir in second cup of chocolate chips
Pour brownie batter into prepared pan, and bake for 20 minutes, or until toothpick inserted in center comes out clean (melted chocolate may be on toothpick)
Remove from oven, spread marshmallows evenly over brownies, and return to oven and broil for additional minute or 2 until until marshmallows are golden brown
Remove from oven, allow to cool slightly, and top with graham cracker pieces and chocolate candy
Allow to cool completely before serving