Discussion Forum—A Way with Words, a fun radio show and podcast about language

Where did the phrase "Easy peasy lemon squeezy" originate?

I found one reference that said, "Hello. I think that the authentic version is: "Easy, peasy, Japanesey. Wash your bum in lemon Squeezy". (it was a detergent with a bizarre spelling)

You would chant this as a child in the playground at school, certainly in the UK (at any point in the last fifty years)."