Place a medium saucepan over medium heat with the syrup. Bring it up to a bubble and simmer until reduced by half, about 10 minutes.
Line a baking sheet with parchment paper or aluminum foil and pour the syrup out onto the sheet in fun shapes. Pop the tray into your freezer and let them set up until firm, about 10 minutes.
Enjoy these fun treats on their own or use them to garnish vanilla ice cream – just be sure to eat them all up within a couple of hours or they’ll go bad in the freezer.