Place the graham cracker in a Ziplock bag. With the back of the spoon, crush it into small pieces and put on a plate.

On another plate, add 2 Tbsp of chocolate syrup and dip the glass in the sauce, followed by the graham crackers.

In a shaker, combine the crème de cacao, vodka, and 1 oz chocolate syrup with ice. Shake for 30 seconds. Add the heavy cream and shake for an additional 15 seconds. Strain into a lowball glass and garnish with toasted marshmallows.