People just generically call it "Sweet Taro bun" which as many people know could mean anything from a bready bun with taro filling to a sticky rice cake with taro filling.
Here is a picture of it:
I had it at DimSum yesterday. It was covered in a white powder. It was sweet. Is made of a homogenous mixture, no distinct filling in the middle. It was covered in white powder and is this soft, not too sticky, ever so slightly purple but mostly white.
I need a more specific name so I may google a recipe. Or I just need a recipe. But I am infatuated.