Add chocolate syrup to a small dish, and graham cracker crumbs to a second small dish.
Dip the rim of your martini glass into the chocolate syrup, and then dip it into the graham cracker crumbs so they stick to the rim of the glass.
Set the glass aside.
Add a large marshmallow to a cocktail pick. You can use it as-is, or toast the marshmallow just after making the drink itself.
Cocktail
Add the cream, chocolate syrup, Bailey's S'mores, chocolate vodka and vanilla vodka to a cocktail shaker.
Fill the shaker with ice.
Shake vigorously, about 15-20 times.
If you want to make the chocolate syrup drizzle, take your chocolate syrup bottle and carefully drizzle it into the inside of the martini glass, moving the glass around while you pour so that the syrup makes a swirl pattern inside the glass.
Strain the drink into the martini glass.
If you're toasting the marshmallow, you can do it now. I used a kitchen torch to toast mine. Just go slow, be cautious and don't burn yourself! You can wear a fireproof glove if you have one.
Rest the marshmallow on top of the drink, and serve!