Ask a tiki historian what “Donn's Mix” was and they'll tell you: white grapefruit and cinnamon, the secret spine of the 1934 Zombie and half of Don the Beachcomber's classified menu. That's what's in this bottle — tart grapefruit, both white and pink, over cane and brown sugar with real cinnamon — the mix Don never explained, ready to pour.

It's the fastest route to a legitimate Zombie or a Donga Punch, and it keeps going: a Krakatoa with tequila, a BG's Rickey with gin, a Devil Reef with something dark. Grapefruit and cinnamon shouldn't work as well together as they do — which is probably why Don kept it a secret in the first place.

Once opened, refrigerate and use within 90 days — unopened, it keeps for two years from the date of manufacture.