Being a Kiwi I hate to let Australians take credit for anything but I will try and be good in this comment
Tim Tams are a Biscuit I think I have only had a couple of times, but I must say the Australians did well with these they are real nice.

Crumpets are very popular both in Oz and NZ, but I have to give credit where its due, they originated in the UK I do believe

Now vegemite I grew up with, and something very similar, Marmite which is the UK version but they had a factory making it in NZ, but both of them are somehting people either love or hate, most of my family here hate it, which is good for me the odd time I find it in a store, as I love it, they all think I am mad as I will happily eat a spoon full of it on its own