The following variant works for me; the Cocchi Americano brings a pleasant bitterness, with a note of cinnamon: 1.5 oz gin, 3/4 oz Cocchi Americano, 1/2 oz crème de cacao, 1/2 oz lemon juice.

The original Tuck recipe was an eye opener, after trying the main recipe above. Completely different! Due to the extra lemon. I think I prefer the Tuck version (I had to sub Tanqueray) which comes across as a riff on a Corpse Reviver #2 with chocolate in place of orange. The chocolate is gone as a dominant flavour note but is still a key part of the overall impact. Mmmm.

Wanted to try this but I tend not to keep sweet vermouth in the house since I have trouble using it up. Eventually settled on a 2:1:1 ratio of gin, creme de cacao, and fresh lemon juice, and then added in a half each of dry white wine and grand ma, together with a tsp of sugar syrup, to try and fill in for the vermouth. I don't think the substitution is especially accurate, but I did enjoy the drink, which came together like a gimlet with additional aromatic complexity from the chocolate

This was very refreshing and a lot drier than I’d expected. Very enjoyable

Surprisingly good. A combination of never think of but it had a very refreshing sweet and sour thing about it. Good for a sunny afternoon.

I've had a few variations on this drink so I was intrigued by this spec. It's very chocolate forward, not in a bad way, but not what I expected from a Twentieth Century. I think I prefer the Meyer variation.