Far, far too sweet for my tastes. Managed to kind of save it with a few dashes of angostura, 10 mL of Laphroaig, and 15 mL of Suze.

I doubled the lime, subbed ginger syrup for the demerera and Pusser's British Navy for the Cruzan Blackstrap (not a fan of the Blackstrap). With these changes I thought this was pretty good.

Made it half the sugar and it was still too sweet, so I doubled the lime. You had better love molasses if you want to like this drink. Personally, I think the Fernet overpowers the Cynar, but really, the molasses overpowers them both. Next time, I'd try my existing changes, plus inverting the Fernet / Cynar ratio and splitting the rum with a dry white rum without molasses -- maybe even an agricole. Or cachaca.

I saw a rendition of this at a local favorite bar of mine using Pyrat XO Reserve. As I love that rum I tried my hand at it at home. One of the best rum cocktails I've had in a long time.

 A bit too sour. I added a dash of Peychaud's bitters and for some crazy reason 1/4 oz Pama Pomegranate liqueur. Maybe too weird, but something sweet might help or maybe lime is too much on original.  Needs a bit of work...

Used Goslings black in place of of the blackstrap. Heavy on raw molasses flavor. Almost has a bit of a charred flavor to me (which i don't mind). Pretty good overall but not blowing me away

I had bookmarked this recipe in Gaz's book years ago as it has several of my favorite ingredients but never got around to making it.  Was searching through his MixologyTech app recently and it popped up again, so decided to give it a whirl.  My first thought was I'd definitely need to make some alterations--the only .25 oz lime must be a misprint (especially after seeing some of the comments here), and I thought for sure I'd have to split the Blackstrap with another dark rum--much as I'm not a fan of the all Blackstrap Jungle Bird--but I first made it as spec'd (excepting I used 1:1 demerara syrup).  And it works, at least for me.  I did try a version with a 1:1 split of Blackstrap to Diplomatico Mantuano and .5 oz lime juice, and the flavors were just muddied and less intense than the original. While the flavor profile is a bit one note, I give it 4 stars for challenging my pre-conceived ratio notion.

Not as wild as I was expecting. The lime really does a good job cutting through all the strong flavors. The savory of the Cynar lends itself well to the brightness of the lime and the spice of the Cruzan. The Fernet clashes a bit with the lime for me, but does link it better to the Cruzan. Not a favorite by any means, but decent and some people will enjoy it

I was pretty sure I'd like this one, but I also served it to someone whose idea of a cocktail requires soda (granted, he needed a strong drink). It really melded beautifully--the spiciness of the rye and sweet fruitiness of the calvados come to the forefront, made richer by the chocolate bitters.

We really liked this cocktail. We used Rye and Bourbon - Bulleit, Prunier VS Cognac, Clear Creek Pomme, Bitter Truth Mole Bitters for the original and thought it was just damn delightful.
Looking to do a punch version for possible fall menu consideration. Any thoughts or suggestions? Especially a beautiful garnish...would love to get our pastry chef involved.

Curated to add Frederic Yarm's website 2008 description of the drink as a reference. Changed recipe to "authentic." Added lemon twist to ingredient list.

I didn't have Greylock Gin and wanted to boost the Boston Bittah's and dry vermouth to give this a more distinctive character, so I used Tanqueray (2), Carpano Dry (1/2), honey syrup (1/4), Boston Bittahs (2 dashes/20 total drops). I was quite happy with the result since the Bittahs' chamomile works complements the honey syrup and the Carpano dry has an herbal forward profile that blends well with the gin's juniper and the twist's lemon oil.

According to the Death&Co cocktail book this cocktail also calls for 1/2 teaspoon of cinnamon bark syrup. The year of creation is set to 2011.

I fixed the year and the syrup. Thanks for the catch!

Zachary

This is a 5 star. I'm paring down my bar to about 15 bottles (not counting repeats like both Chartreuse or clear and aged rum) and mezcal didn't make the cut; I don't use it enough or love it. With this drink though, that's a sad thought. I did use regular syrup because I don't have cinnamon.

How about "Rhymes with Lime"?

I used your recipe but altered it a bit and it turned out really good.  I didn't have grapefruit bitters but used rhubarb bitters instead and added grapefruit juice instead of lime juice. Really good. Thanks.

Thanks for the posting. My proportions: 1 oz. gin, 1/2 oz. all other ingredients except a few drops orange bitters and a touch of sweetener.

Curated to revert recipe to the original as described by Wikipedia, which did not have bitters. Moved bitters to the Notes section.