I'll have a double dozen, double damask, dinner knapkins

Jan de Casalis has a lot to answer for.........

Try asking for a bakers dozen - and just to be jocular (assuming they know what that means) I sometimes ask for a metric dozen. The old ones get it - mostly.
But then when I wear Black & White and youngsters ask why I am not in red I can't tell them it is the same old joke - disguised as a newspaper (black & white & read all over) because they ain't black and white no more. It's called progress.

What I would say to the teenager would be "Tell you what, you give me 6 and I'll eat half a dozen and we can see how many are left" but if you really want to be snotty - add "if you can count that high"