I hoped that if I baited my hook with footnotes, a Food Historian might bite: and hooray! it worked!

So, German / continental style gingerbread it is. What about the gold paper stars? I would so love for them to be real...

And I agree that there's nothing inherently unlikely in Mary Poppins taking on any of the tasks she does; what interests me is the way that the narrative wants Mary to do everything, and doesn't mind that there is nothing left for other people tp dp.