Dip rim of glass in chocolate then crushed graham crackers. Place glass in freezer until ready to serve.
Pour all liquid ingredients in shaker with ice and shake until well mixed.
Pour into chilled glass and sprinkle with some graham cracker crumbs. You could get "fancy" and take a large marshmallow, spear it with a small drinking straw then coat it with chocolate syrup and marshmallows. Place straw/marshmallow in drink and enjoy!