Lorde Birthday Buns in New Zealand

11/8/2014 10:25 AM PST

Lorde -- Birthday Buns in New Zealand

Lorde celebrated her 18th birthday Friday in New Zealand with her boyfriend ... and their matching buns.

The young singer hit up a cafe in Auckland yesterday after officially becaming legal ... but we're guessing she probably didn't buy cigarettes and porn ... or go to the strip club.

Lorde's BF James Lowe -- who reportedly worked as her photographer before they started dating -- once said dating the famous singer has been a whirlwind from all the attention.

At least the dude's got a sweet ponytail.