1 tablespoon graham cracker crumbs, or as needed
2 fluid ounces chocolate liqueur (such as Godiva®)
2 fluid ounces half-and-half
1 1/2 fluid ounces marshmallow-flavored vodka (such as Smirnoff®)
1 1/2 ounces Irish cream liqueur (such as Baileys®)
4 miniature marshmallows, lightly toasted, or more to taste
1 small cocktail skewer
Pour graham cracker crumbs onto a small, shallow plate. Moisten the rim of a chilled martini glass and dip the moistened glasses into the graham cracker crumbs.
Fill a shaker with ice; pour chocolate liqueur, half-and-half, vodka, and Irish cream over ice. Shake until cocktail is combined and strain into prepared martini glass. Thread marshmallows onto a skewer and garnish cocktail with marshmallows.