TS. i think it started from the "Mr Brown's" podcasts..
one of his first few podcasts was the episode " Ba Chor
Mee"...
he went up to the counter and said, Ba chor mee, mai hum... and
so on.
this was actually a pun, regarding the governence in sg.
.
.
.
then... later PM give speech, about mee siam, and got edited by
Mr Brown, becoming Mee Siam Mai Hum
hahahahhaa
PM lee deserves it!