I test it but for, my taste, I prefere the following proportion:
1/2 shot of bourbon
1 shot of aperol
3/4 shot of nonino
3/4 shot of lemon juice.
We used the same trades described.
Maybe if we get a different aperol or different Amaro or different bourbon I will change proportions.
It is funny to ask friends toale the paper airplane while you prepare the drink. Creates a good mood between people and if drink is already high, it will make laughs

They say don’t mess with a good thing. In this case a great thing. But I kinda want more bourbon.

Works extremely well with Amaro di Angostura!

I had my first Paper Plane (or Paper Airplane) at a brewery in eastern Iowa, a couple of years ago. Thought I had died and gone to heaven!
Sadly... it's not a well known cocktail and I've not come across a bar where they know how to make one. Many will not go off menu so I can't even get them to make one. Glad I'm mostly a home- cocktail drinker! (Cheaper that way anyways, LOL!!)

Each weekend, starting on friday: I sound a bell, and the bar is open in the office. Nobody can leave earlier just because is the last day, but the challenge is they can order and I can make anything they ask. 12 people, several hours. And then the weekend. Maybe I make around 40 recipes a week -hey is just my hobby- but of all those maybe I only remember, the Last Word, the Paper Plane, the Aviator, the Naked and Famous, and some classics. Thats the importance of the PP.

Love the bitter notes in this LW riff. The aperol opens up the stage for the bourbon notes, and the amaro is just heaven in this. (To be fair, I'm already a nonino fan.) Really structurally tantalizing.

Enjoyable. I upped the bourbon a little; next time I think I will up it a more.

If you don’t like or can’t have bourbon, Absaroka Double Cask Gin 49 is a WONDERFUL alternative. I’m sure other barrel aged gins would be good. Absaroka is just very mellow and perfect for this cocktail.

So Antoni makes a point: how does this "riff" have no ingredients in common with the 'Last Word" Is it just the proportions, because I am sure we could name dozens of other drinks with the same proportions.

First of all, I completely disagree: THIS IS NOT a Last Word riff. Are we saying that every single cocktail that has 4 ingredients in equal proportions, one of them lime/lemon juice, other one a strong spirit, is a Last Word riff? DEFFINITELY NOT. This one is a very different cocktail. In my (modest) opinion, what make this drink different is the use of two amari. Said this, I didn't have Nonino in hand, and a populr AI suggested Averna. Moreover, it suggested different proportions and bitters. So I went with :
1.75 oz bourbon (Buffalo Trace)
1.25 oz Aperol
1 oz Averna
1 oz lemon juice
2 dashes of Regan's bitters ( its election over Angostura orange, Scrappy's, Fee Brothers, Fee Brothers Gin Barrel Aged, Bitter Truth)
Excellent cocktail! And please, I'm a Last Word lover, and this cocktail has anything in common at all. Love U all, cocktail lovers