How to Make A Toasted S'Mores Cocktail (Cocktail Chemistry)

Straight up perfection. A dessert cocktail, yes, but it's well-balanced.

Recipe
2 oz Cacao Rum
1 oz Sweet Vermouth
Angostura Bitters
1/2 oz Mandarin Orange
1 Sugar Cube
1 Marshmallow
1 Dash Peppermint Extract
Chocolate Magic Sugar Rim
Crushed Graham Cracker