OK, so what is it made of, and what does it taste like?
It’s made of yeast and salt. It sort of tastes like very salty soy sauce paste.
North Mountain gave a pretty good description. The British have a similar product called Marmite, but not as good. If you grew up with it, you probably like it; if not then you’ll probably revile it.
Normally spread very thin and splotchy as it has a very overpowering flavour. Most Aussies have a cruel sense of humour and will give Americans a full spoon to try. Almost no one will enjoy it this way.
It is a staple item found in the pantry of most Australians, in fact I need to buy more when I go to Costco this weekend as I’m running out. It is also a great flavour enhancer for soups.