Akizuki broke apart a pon de ring donut and stacked it to make it resemble a traditional image of mochi stacked onto a pedestal (the example I linked uses a pile too, but it's common to see a two-three-layered kagami mochi with an orange on top). I am uncertain what the pedestal is called and we don't have a tag for it. We seem to associate the image of it with the tag wagashi often, though that refers to a variety of confectionary including mochi, not the presentation of the mochi.