Even more awesome earlier, because there's only the bottom third or so left. This is the sterile base, left after all the purplish spores have been blown away and an example of an earlier stage is here: http://canberranaturemap.org/Community/Sightings/Details/2459154
The remaining purplish spores say either Calvatia cyathiformis or Calvatia lilacina (if you want to keep the latter a separate species from the former). The breadth of the ‘cup’ suggests that there is a robust supporting base beneath and that points to Calvatia cyathiformis.