Help! What does boiling water do in sponge cake recipe?

[Floweryfields]

I just realised I forgot it - and cake is half cooked will it be okay?

[buffy1]

A bit late, but I think it gives the sponge a more tender crumb.

How did it turn out ausgirl? Am sure it was delish!

[~me~]

It lightens I think? My Mum always used to put a teaspoon of boiling water in most of her cake recipes at the end of mixing.

[Floweryfields]

It was a disastorous flop! Totally sunk in the middle and remembering back, I realised I had the same failure with the same recipe before. So I started again with the fielders cornflour packet recipe and it was a great success!