"I'd rather be with your friends mate 'cause they are much fitt-ar," she sang in 2007, defining a summer in the most irritating mockney fashion imaginable. I'm sure she's a lovely girl, but good God, it was annoying.
So what has Kate been working on since then, in between hanging out with her rock star boyfriend? Has she taken the Lily Allen route - cheesier music, snarkier lyrics?
No. 'I Just Love You More', available as a free download on her site, sounds exactly like the Pixies, fronted by PJ Harvey. That is to say: absolutely brilliant.
It opens with a chug of distorted guitar, before big drums and a killer riff kick in. Is this really Kate Nash? "I just love you more than anything", she moans rather creepily, sounding thrillingly desperate and obsessed, before letting out a demented shriek of pain as the guitar wails with feedback.
Then things build to a nightmarish crescendo before abruptly ending; we are left only with Kate panting, out of breath from her emotional exertions. Astonishing. If she carries on like this, her album might just be worth listening to.
Her new single, drawn from her soon-to-be-released second album, reveals new listening habits: riot grrrl and punk, Phil Spector and Motown. Now Nash's musical arsenal includes curdling shrieks, a sharp-fanged guitar, and wordless strands of ba-ba-ba's.
Whether you view this as a return flight-- it has something in common with first single "Caroline's a Victim"-- or a brave departure into darker places, "I Just Love You More" is destined to divide listeners.
Fans of more recent Nash are accustomed to warmly impolite pop songs that set deadbeat lovers in their sights and pull the trigger. This will leave them cold and confused.
Meanwhile, those inclined to punk fireworks may simply turn to Karen O-- the unglued genuine article.
Sewing these attitudes together, in short, is a dangerous move for Nash. But look past the wrong turns near the end and you'll find the blunt, lovelorn girl who charmed us three years ago. "I Just Love You More" startles with its union of vulnerability and vigor.
In fact, the sentiment here -- a lusty declaration? an appeal for requited love? a parting shot? -- is thrillingly tough to pin down.
The spooky, spiky riffs and slicing strings, her jungle howls and dazed refrains, impart the fury, at the song's burning climax, of a girl group scorned.