Coupe or stemmed glass, and which size
The standard build is five centilitres of vodka, three centilitres of coffee liqueur and a fresh espresso of about three centilitres. Shaking adds meltwater on top of that, so you strain twelve to fourteen centilitres into the glass, foam included. A bowl of 20 to 24 cl is the sweet spot: full enough to look generous, with just enough rim above it to keep the beans dry.
Anything over 28 cl gets tricky. In a 30 cl coupe the same volume of liquid spreads across a wider surface, so the foam layer thins out and breaks sooner. If you do want a large glass, shake one and a half servings. Smaller than 15 cl works too, and that is exactly what a nick & nora is: that bowl sits here among the other shapes because it handles the same cocktail in a more compact serve. Pay attention to the rim as well. A thin, tempered rim feels better against the lip than a thick one, and with foam you notice that difference more than with a plain drink.