Bring 1 inch of water to a simmer in a pot. In the bowl of your stand mixer add egg whites, sugar and salt, whisk to combine. Place bowl over the simmering water making sure that the bowl fits tightly but the bottom of the bowl doesn’t touch the water.
Heat the sugar mixture, whisking frequently, until a candy thermometer reads 120° F or they are hot to the touch. Remove bowl from heat and place in the base of your stand mixer fitted with the whisk attachment.
Beat the mixture until cool and glossy. Add the vanilla and cinnamon (more to taste), and beat to incorporate.
Spoon into a large piping bag fitted with your favorite tip. I used a Wilton 2D for these sticks.
While the whites were cooking, make your ganache by combining chocolate and heavy cream in a microwave safe bowl. Microwave on 50% power in 10 second increments until the cream is hot and the chocolate has begun to melt. Remove and whisk until smooth. Whisk in the vanilla.
Using an offset spatula or a knife, smear a little chocolate on each graham cracker section. Allow to cool before piping frosting on each.
I toasted mine with a blow torch (a mini one, Nana) but you could also do it under the broiler.
Notes
Recipe for the Marshmallow Frosting adapted from http://www.chow.com/recipes/30784-marshmallow-frostingThis frosting recipe will frost 16 cupcakes or makes 48 mini sticks.