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I believe we've done the work to call this the ultimate Gin and Tonic recipe.
After several attempts to make an exceptional homemade tonic syrup - including this famous recipe from Jeffrey Morgenthaler, and this one from Lottie + Doof, via Tony Cecchini and the NYTimes - Keith and I were unsatisfied. In all cases, we liked the tonic, but we didn't love it. Our biggest complaint - we couldn't taste the gin.
Gin is divisive, isn't it. Do you know anyone who's on the fence about it? People seem to either shrivel in horror or swoon with delight at the mention of it. Those who swoon like the flavor of gin, and why? Because it's loaded with botanicals - primarily juniper, but look at this list of other essences you might experience.
After each attempt at a homemade version, we would end up back with our favorite store-bought tonic, Fever Tree Naturally Light. It's light, not in a phony sugar way, but in a less-sugar way - a plus as most store-bought tonics are ridiculously sweet. It's only slightly bitter, and has a fresh citrus flavor. But it's also understated, too much so once you've tried a homemade version. So it was our muse, but we hoped for something even better.
How to Make Tonic Water
We started the experiment to create our own recipe with 3 criteria:
- The syrup had to be delicious, but subtle enough to accentuate, not overpower the gin flavor.
- It had to be cold extracted because cooked citrus zest tastes, well, cooked.
- It needed to be just barely sweet and pleasantly bitter.
We decided to try 2 versions - both had the basics: cinchona bark (the natural source of quinine), and citric acid (necessary for extraction and helpful for preserving).
The first version had just citrus zest and lemongrass. The second had zest, lemongrass, and other botanicals: cardamom, lavender, allspice.
We filled our jars with filtered water, shook them daily, and allowed them to steep for 72 hours. I firmly believed that the version without the additional botanicals would prevail.
I was wrong, sort of.
Think of vanilla extract. Take in that incredible aroma and you're tempted to take a swig. Or you were tempted before you tried it straight the first time. On it's own, the extract is bitter and pungent. But in the proper proportion, added to a sugary or savory recipe, is matchless. Tonic syrup is like that.
You can't try a couple of syrups straight and determine which is superior. You have to make a proper drink and try them side by side. Work, work, work!
We did our careful taste-testing and were surprised by the result. Both were excellent. Both were missing something. So we took a chance and combined the two. And, Success! Really, the BEST gin and tonic either of us had ever tasted.
What began as rivalry ended in alliance.
More Classic Cocktails
And if you're interested in trying other delicious classic cocktails, I recommend the very herbaceous Last Word Cocktail, this Boulevardier Cocktail recipe, this Peach Bellini recipe, and this French 75 Cocktail!
Recipe Update: Several people asked about ingredient weights and I finally got around to weighing as I went - because really, there can be a huge difference in size from one citrus fruit to another or between stalks of lemongrass.
I've also increased the amount of rich simple syrup based on recommendations (looking at you, Ken Smith 🙂 ), from several people who commented on the original post - it still only comes out to be 1 ½ teaspoons of sugar per drink and really does make for a smoother, more balanced flavor. However, if you prefer your tonic more tart / bitter, stick with the original amount of syrup: 2 cups sugar and 1 cup water.
Homemade Tonic Water Recipe Video
Homemade Tonic Water for the Ultimate Gin and Tonic
- 3 cups water (675 ml)
- ¼ cup chopped cinchona bark (1 ounce / 28 grams)
- ¼ cup citric acid (2.2 ounces / 62 grams)
- 3 limes peeled zests only (0.4 ounce / 11 grams)
- 3 lemons peeled zests only (0.5 ounce / 14 grams)
- 2 oranges peeled zests only (0.5 ounce / 14 grams)
- 3 stalks lemongrass tops and bottoms trimmed and outer leaves removed then sliced into ⅛" to ¼" rounds (2.5 ounces / 71 grams)
- 4 whole allspice berries
- 3 whole green cardamom pods
- 1 tablespoon lavender
- ¼ teaspoon kosher salt
Rich Simple Syrup
- 3 cups natural cane sugar (21 ounces / 600 grams)
- 1 ½ cups water (355 ml)
You'll also need:
- Lime wedges
- Sparkling water
- Combine all ingredients except rich simple syrup in a sterilized, one-quart lidded glass jar. Shake to combine. Refrigerate 72 hours, shaking occasionally, at least once per day.
- Make rich simple syrup: dissolve 3 cups sugar in 1 ½ cups water over medium heat until sugar is completely dissolved. Allow to cool. Transfer to a container and refrigerate.
- After 72 hours, strain tonic mixture into a large glass pitcher. Strain tonic a second time, using a coffee filter or very fine cheesecloth.
- Whisk simple syrup into tonic until thoroughly combined.
- Pour tonic syrup through a funnel into storage bottles and store in the refrigerator.
For the Ultimate Gin & Tonic
- Fill a highball glass with ice. Add 1 tablespoon tonic syrup, 2 ounces gin, and 2 ounces sparkling water. Stir to combine. Serve with a lime wedge (about ⅙ of a fresh lime). To drink: squeeze the lime wedge into the drink, then drop it in. Enjoy!
I made my first batch of your Homemade Tonic Water and it is spectacular! My wife and I have been enjoying Gin & Tonics more than usual this summer as we've had several days of over 100-degree weather. I like Canada Dry but became frustrated when everyone seemed to be out of it wherever I went. That's when I decided to go it alone and make it myself.
I tried another recipe first but it was way too sweet. With your recipe I held off on combining the rich simple syrup with the botanicals in case the ratio was off for our taste buds. After 72 hours of cold extracting I didn't want anything to go to waste!
After a bit of tinkering I made a mini-batch of 3/4 cup botanicals combined with 1/2 cup rich simple syrup. Seems perfect for us!
Thank you so much for posting this. It's truly delicious and a game-changer!
Marissa Stevens says
I love to hear this, Alec! I'm so happy to hear that you're enjoying the recipe and making it your own!
Just wanted to know for the spices.. allspice, cardamom... do they need to be crushed?
Hi, Fred. No need to crush them... Cheers!
Hi, I made the tonic during the week, yesterday it was ready, I prepared a little batch of syrup.
After reading all comment I had high hopes and was a little disappointed, but I think that the problem was the sparkling water... a newly opened san pelegrino bottle, but it lost it's bubbles to quickly, so my G&T was a little bland, it was like gin diluted in water with bitterness... So next time I'll try prerier and maybe a soda stream from a friend, it really needed more bubbles.
Also my simple syrup wasn't made with cane sugar, which is something that also give some flavor, so that's my fault, I triedwith Erythritol which is a zero calories sweetener to use like sugar.
I made some tonic water about three weeks ago for Christmas presents. Overall I loved it, next time I'll adjust the ratios a bit and use less sugar syrup (it come out with a distinctly marmalade note!)
However, since then all three of my jars have developed strange white clouds. Has anyone else experienced this? Are they now spoiled? They've been stored in the fridge. The taste is still fine - I drank some before realising.
Thanks for anybody's advice. Google is no help on this one!
Hi Alex. I haven't had that happen and, honestly am not sure who to ask about it. Have a look at this article.
Hi, I'm really looking forward to trying your tonic, I've just made it and it's in the fridge infusing, day 1... I was just thinking about the sugar syrup and that I do tend to drink sugar free tonic on the whole. Have you or anyone tried using a sugar substitute to make the syrup and if so did it work? I'll probably give that a go with a part of the first batch in a few days. Thanks.
Hi Darren. That's so great! I hope you love it...On the sugar substitute, I honestly don't know. I think you have the right idea about trying it with a small amount before adding it to the whole batch. Cheers!
Lisa Alony says
Thanks so much for posting this recipe. I LOVE Fever Tree tonic so I'm glad you were attempting something similar. I'm going to try it very soon. I will be using dried lemongrass instead of fresh since it's difficult to come by and VERY expensive!!
I have a QUESTION: for the dry ingredients, can I measure by the cup or is it better to weigh it?
Hi Lisa! I haven't tried this with dried lemongrass before, but I'd love to hear how it goes. I found this blurb at Chowhound: "When using the ground powder (sereh) use one teaspoon as an equal to one stalk of fresh. It is advisable to soak dried sliced lemon grass for two hours before using." As for the other dry ingredients - I think weighing them is best, but don't worry if you add a little more of this or that.
Lisa Alony says
Thanks, Marissa. What a quick response!! I will soak the dried lemongrass and will post about the results. Will try to get a food scale too!
Have a wonderful weekend!
Constantin Graeser says
Does Point 4 mean: Mix the Rich simple syrup with the "tonic+lemon+rest which stayed for 72 hours" thing ? Or what is number 4. Sorry I am from Germany. So I think that I have to combine the syrup with the self made Tonic water, isn't it? Thanks for reply.
Hi, Constantin. Yes, exactly. Combine the syrup with the tonic water that you've made.
Susan - saf affect says
I made this tonic syrup for the first time at the start of this summer and imbibed in more G&Ts (or Tonic & Gins I call them as the syrup is so yummy!) this season than I've had my entire life. 🙂 The hot, hot summer here in Toronto helped them go down real easy!
We use our Sodastream, mixing as we go, not mixing the syrup in an entire bottle of bubbly water. Our formula of 1.5 tbsp of syrup to 1.5 oz gin, to 3 oz Sodastream water (made extra bubbly) with a squeezed lime wedge is delicious. I prefer 3 ice cubes, my boyfriend prefers 2 cubes. And we serve them in the Spanish style in large red wine glasses. Makes a huge difference in enjoyment.
Thank you again for a fabulous recipe that others have now been making requests that I make it for them. I'll be busy!
Susan - saf affect says
Oh, and my motivation for making this was frugality, wanting the best for less - I had tried a sample of '3/4 OZ.' craft tonic syrup the summer prior and when I learned the price, I figured I could make it for less. And it's even more delicious!
I love it! Thanks for coming back to let me know. 🙂 Cheers!
Jo-Anne Mason says
Thanks so much for this recipe. I ordered the cinchona bark on amazon, living in Caribbean limits what is available but the lavender, is that lavender buds? I will order them too.
I am so tired of throwing away plastic tonic bottles that I am even going to try and make the carbonated water.
Looking forward to trying this we love gin and tonic.
Hi Jo-Anne! Yes, lavender buds. 🙂 I'd love to hear how it goes...Cheers!
Jo-Anne Mason says
Hi Marissa, I tried earlier but got bounced off the internet. (just in case you got it) Anyway, we did it, the results are fabulous and we couldn't wait the 72 hours because yesterday was G and T day. I cooked it a bit to speed up the process.
Thanks so much for this recipe, we will use it now as our standard. I even got a soda siphon.
I am curious about the history of tonic water as all I can find on the internet is quinine, lime, sugar and soda water. Is there a better explanation of all the herbs and spices that go into this delish concoction?
Fantastic, Jo-Anne! Thanks for letting me know. On the herbaceous concoction, I think it was to disguise the bitterness of quinine which was originally to combat malaria. Of course a little gin doesn't hurt either. 😉 Cheers!
I'm the biggest G+T fan but fed up with store bought tonic water as it usually too sweet. Fever Tree is good but very expensive up here in Canada. I'm determined to make your syrup recipe. Could you just clarify which cardamom pods you use - green or black?
Hi Ann. Green cardamaom and thank you for asking. I'll call that out in the recipe too. Let me know how it goes. Cheers!
Thanks for posting the recipe and the photos. I just made this; my friends were very impressed. It didn't especially taste like tonic, although it was very good. I used powdered cinchona, and the infusion got quite brown. But it didn't have that nice bitter quinine flavor.
It was very, verytangy. I would try halving the citric acid.
I also (luckily) didn't add all the simple syrup at once. I ended up using only half and it was plenty sweet for me.
BTW, it's also great just in iced water or soda without the gin.
i agree, adding too much of what i ended up with to the drink made a mountain dew. enough was proably a 1/4 teaspoon if not an eitght. i used the original syrup recipe with more water but still became cloying.
i subbed ~equivalent grams of pasted lemongrass as there was no stalks. one problem i had was that straining was exceedingly difficult. it ran through a cloth, used for beer and cheese(i forgot the fabric name) but it wouldn budge in a coffee filter, i left it for an hour and a few spoons made it through. sitting in the fridge it developed clouds of sediment perhaps lemongrass particles. im going try to gin up some traditional tonic water with a flavored simple syrup. i only used cardomom but have had a great cardomom g&t in a bar that was crystal clear vs dew yellow.
but thanks for the recipe, author
Peter Braun says
Thank you for the recipe - sounds very interesting and I will definately try it very soon. I was wondering if you had gotten around to converting the amounts into weight? That would eb an awesome help, especially for us Europeans 🙂
Thanks in advance,
Peter from Denmark
Nick Costidakis says
Have you ever used a SodaStream maker to make a full liter of tonic, If so, how much syrup would you add to make a liter bottle of tonic??
I haven't, but that's a great idea! Let's do the math:
1 drink has 1 tablespoon tonic syrup (1 fluid ounce) and 2 ounces of sparkling water - so about 3 ounces of liquid per drink.
1 liter is ~34 fluid ounces or just over 4 cups. With the ratio above, I would go with 2 2/3 cups of water and 1 1/3 cups of tonic syrup.
If you try it out, please come back and let me know how it goes! Cheers!
john h mantis says
we tried the mix with Soda Stream and it was fine,but lost fizz before we could use bottle up...admit only 1 G&T daily.
The other thing I tried was pouring 165F water into zest mixture....no burn and seemed like better extraction.No matter,way better than store stuff.Thanks for recipe!
Andrea E says
I'm still a bit confused by the recipe. The ingredients list says 3 cups natural cane sugar (21 ounces / 600 grams) and 1½ cups water (355 ml) but the instructions say 2 cups sugar in 1 cup water. Which are you using for this particular recipe? Thanks, Andrea
Oops, my mistake. When I updated the ingredient list, I missed the numbers in the instructions. It should be 3 cups sugar to 1 1/2 cups water. Cheers!
I just made this last week and it turned out perfect! I used a bit less simple syrup than called for (that much sugar freaks me out a little), it turned out tart and wonderful. Thanks so much for sharing the recipe!
That's fantastic, Abbey! Cheers!
Charles Glendinning says
One thing that kills any drink that needs ice is using the milky junk that most refrigerator ice makers produce. That milky look? Air bubbles. Where does that air come from? Inside your refrigerator... bits of compost in the bottom of the vegetable drawer... cheese mold... any container of leftovers way in the back with a layer of fuzz on it. It's all in the air of your refrigerator. A bag of ice at 7-11 costs... what... 1.69? It'll probably last 2 weeks and will be the best thing you ever did for your mixologizing, AND it's crystal clear! Taste and looks! Win-win!
Er, the air is dissolved in the water before it is frozen. On cooling it comes OUT of solution and forms bubbles in the ice. If you want bubble free (and pretty much taste free) ice, boil it first to drive off all that nasty air. Your water supplier also adds a few things which will alter the taste. If you really want nice water, come back to the Scottish highlands and use fresh free running water from the burn. Nothing tastes better in Whisky!