Milk on the side?

Went to Pizza Express tonight - probably the best restaurant that is part of a chain - had my usual American Hot, and then asked for a 'long black with milk on the side'.

The waiter wasn't quite sure what a 'long black' meant - but having come back from Oz I realised the mistake was mine. So I asked for an 'Americano' and got what I was after.

As for the milk - I'm not sure what coffee to milk ratio he was thinking I would enjoy, but perhaps he though I was being joined by another ten people all wanting milk in their coffee.