I think That it may be an Usher track as that name keeps popping up in searches.
I have one advert song I've found:-
Jaffa, Jaffa, Jaffa, Jaffa
Now listen general public for goodness sakes
my family they go crazy for these jaffa cakes,
like when I’m bouncing little baby on my knee,
the first words that he speak were ‘they’re orangey’,
My wife she say I’m crazy need to see a shrink,
he prescribed two a day with a nice hot drink,
it’s the spongey bit for granny she lose all control,
I can’t see it myself cos I like a fig roll.