Hi Lucy,
My mum used to have this all the time when I lived back home. She would often use it as a sauce for stir frys which may sound weird but it worked.😛 It's often recomended as being 'healthy' which is why I think my mum uses it! Don't know what it's supposed to do though!
I saw it in Tesco the other day but I know my mum gets it from her local health food shop and Holland and Barrett sell the powdered sachets with little chunks of Tofu in.
x