This is the classic tonic water recipe floating around the Internet. I personally find it a bit complicated and the lemongrass puts me off but you may like it better.
Ingredients
- 4 cups water
- 1 cup chopped lemongrass (roughly one large stalk)
- 1/4 cup powdered cinchona bark
- zest and juice of 1 orange
- zest and juice of 1 lemon
- zest and juice of 1 lime
- 1 tsp whole allspice berries
- 1/4 cup citric acid
- 1/4 tsp Kosher salt
Instructions
Combine ingredients in a medium saucepan and bring to a boil over high heat. Once mixture starts to boil, reduce heat to low, cover and simmer for 20 minutes.
Remove from heat and strain out solids using a strainer or chinois. You’ll need to fine-strain the mixture, as it still contains quite a bit of the cinchona bark. You can use a coffee filter and wait for an hour or more, or do as I do and run the whole mixture through a French coffee press.
Once you’re satisfied with the clarity of your mix, heat it back up on the stovetop or microwave, and then add 3/4 cup of agave syrup to each cup of your hot mix. Stir until combined, and store in the attractive bottle of your choice.
You now have a syrup that you can carbonate with seltzer water; I use my iSi soda siphon for some nicely-textured bubbles. To assemble a gin and tonic, use 3/4 ounce of syrup, 1 1/2 ounces of gin and 2 ounces of soda water over ice.