[JohnW]

This was a little jingle also. It was probably one of the first adverts on British TV. I remember the richer kids at school singing the jingle in the first weeks after the introduction of ITV. We only had BBC at our house. I would estimate this was 1955.
You're looking for two words. One is the product and the other is the manufacturer. This stuff is definitely still around!


--------'-, --------'-, they make the finest -----,
It is the brightest and the lightest that's --------'- -----,
Your pastries are tasty, your cakes are rising too,
And what's the ----- that never varies, that's --------'- too.