Phenomenal! I am impressed at the creator's thought to combine these items. If you have the ingredients which are cheap if you want it to be, make it!

I found this to be very sophisticated and delicious. I will totally make it again.  But what color is it supposed to be?  I used gold rum and did not have the "right" kind of sherry (I used amontillado), so it might be my fault that it turned out kind of grey.  (I mean, looking at the title, it's supposed to be blue I assume? : -) 

This recipe is from Pioneers of Mixing at Elite Bars: 1903-1933, and the blog post was:

https://cocktailvirgin.blogspot.com/2012/03/blooey-blues.html

I can't help but wonder whether it would be better with an agricole and a fino/manzanilla sherry (opposed to cream sherry -- Lustau East India Solera -- that I made it with).

Curated to add source to Reference section. Thanks!

I used Brugal rum and Amontillado sherry. Very nice idea, but my balance was off - too much lime for me, and I upped the rum. That helped. Can't find that sherry, so I'll try with others or maybe just Punt es Mes or other vermouth. Color was ugly gray/green but I like that!

Made with Rock Rose Gin, two large basil leaves, and a toddler-sized handful of thyme. My husband said it could have had a bit more simple syrup, but we both agreed that, despite tasting a bit strong, it's a very refreshing drink and we love that it utilizes ingredients from our cocktail garden.

Curated this. Removed the long quote from Toby for copyright reasons - it's at the cited link. Added the grapefruit peel garnish, removed "fresh" from lemon juice... we know better. Rewrote instructions to avoid copyright. As an aside, this develops grapefruit flavors without the use of grapefruit - I'm not sure that adding the grapefruit bitters is necessary. Thanks,  Zachary

Excellent cocktail! One omission from the original recipe is a lemon peel, expressed and discarded.