Last week I was in Sacramento reporting on the local cocktail scene for Tasting Panel Magazine. We stumbled into Ella, a fine dining restaurant where the signature cocktail is a gin and (homemade) tonic.
I've tried several versions of homemade tonic water and even made my own, and to be honest none of them were mind-blowing. Schweppe's Indian Tonic is better. But this one at Ella is terrific and fresh, and the secret is... not to make it into a syrup first.
Bartender Chris Dooley made the drink by adding ground cinchona bark powder - probably 1/8 teaspoon of it or less- to an empty glass, then adding the gin (209 Gin in their case), lemon and lime juice, cane sugar syrup, ice, and soda water.
Dooley said they found cinchona bark powder doesn't dissolve well into anything except the gin, which is why they put it in before the other ingredients. That said, you could still see particles of the bark powder at the bottom of the glass. Yet this drink didn't taste as barky as the syrup that I made, even though I ran it through coffee filters a couple of times. It was fresh and bitter and really good.
I haven't tried to replicate the drink at home yet, so please let me know if you've made it work (or not) this way. It would be hilarious to find out in that trying to get the tonic into syrup form people have been overthinking what could be simple homemade tonic water.