"'S e aran milis a th' ann."
Translation:It is shortbread.
To add to SrGI2aed’s answer – this also works for other persons, eg. ’s e dotair a th’ annam I am a doctor (it’s a doctor that is in me), ’s e tidsear a th’ innte she is a techer, etc.
The copula is often omitted: dotair a th’ annam, tidsear a th’ innte
It’s possible to just use the copula directly, but I think it’s less common (rather literary/archaic usage): is aran milis e it is a shortbread, is dotair mi I am a doctor, is amadan thu you are a fool. This is much more common in Irish.
Also one can use the copula with adjectives, but that’s very archaic/poetic and emphasizes the adjective: is brònach mi I am sad.