Cinnamon syrup is simple syrup simmered with cracked cinnamon sticks and left to steep, giving a plain sugar syrup a warm, baking-spice edge. It doesn't carry the Beachcomber-era pedigree of orgeat or allspice dram — it's a newer, more utilitarian fixture of the modern craft-tiki pantry, the kind of syrup a bar builds for one house drink and then keeps around because it's useful everywhere.
Why Make It
There's no well-known bottled cinnamon syrup on most bar shelves the way there is for grenadine or orgeat, so a homemade batch isn't really competing with a commercial version — it's mostly filling a gap. It's also one of the fastest specialty syrups on this site to make: no infusion wait, no straining fine sediment, just a short simmer and a steep.
The Build
Cracked cinnamon sticks simmer briefly in a 1:1 simple syrup, then steep off the heat to pull more flavor without over-reducing the syrup.
Sticks, Cracked
Whole cinnamon sticks, broken into a few pieces rather than left intact, expose more surface area to the syrup. Ground cinnamon works in a pinch but leaves the syrup cloudy and gritty even after straining through cheesecloth.
Cassia Versus Ceylon
Most supermarket "cinnamon" sticks are cassia — bolder, sharper, more assertively "cinnamon-red-hot" in flavor. True Ceylon cinnamon is softer and more delicate. Either works; cassia gives a more forward syrup, which is usually what a rum-and-tropical-fruit drink wants.
Storage and Shelf Life
A plain sugar syrup base keeps reasonably well — about three weeks refrigerated in a clean jar — though the cinnamon note softens well before the syrup spoils. Taste before using an older batch and expect to top up the spice with a fresh stick if it's gone flat.
Bottom Line
Cinnamon syrup is the easiest specialty syrup on this site to make and one of the most versatile — it earns its keeping a jar around well beyond the one recipe that sent you looking for it.