Serious Eats: Recipes
The graham cracker recipe is adapted from Liz Gutman's fantastic version. The marshmallows are a revised version of this practically instant-setting marshmallow recipe from Peeps Week '09. It allows just enough time for the graham sandwiches to be made before the marshmallows set. You'll need space in your fridge for one or two wire cooling racks covered with cookies.
If graham flour isn't readily available to you, you can substitute whole wheat flour.