Bittersweet

Angostura on its own turns it darker and more medicinal. Orange bitters on its own makes it prettier and less interesting. Together they bracket the two vermouths at either end. If you only own one bottle, use Angostura and add a wide strip of orange peel to compensate.

You get a paler, softer drink that leans on vanilla and elderflower rather than the bitter, spiced end of a red vermouth. It also loses the color, which is half of what makes the glass look like a drink. Fine in summer. Add a second dash of orange bitters to put some edge back.

Fifteen milliliters of a London dry is the line for me. Beyond that you have a Martini with both vermouths in it, and the reason for the drink evaporates: being able to have two before dinner and still cook afterwards. Keep the bitters whatever you do.

Soda, mostly. An Addington takes the same two vermouths and stretches them with 60ml of soda water in a wine glass, which gives you something long and quenching. This one keeps them concentrated over ice and pulls the whole thing in a bitter direction instead.

A classic Bittersweet calls for 45 ml (1.5 oz) Sweet vermouth, 45 ml (1.5 oz) Dry vermouth, 1 dash Angostura Angostura bitters, 1 dash orange bitters Orange bitters. That single-serve spec scales cleanly — the recipe above converts it to oz and multiplies it for 2–4 drinks.

A standard Bittersweet is roughly 17% ABV once mixed (before ice melt softens it further). That makes it about as strong as a glass of wine.

A Bittersweet is shaken. About 13 seconds with plenty of ice chills and dilutes it correctly.