I just bought some from
Hewn in Evanston, and they're very good! They call them "neapolitan cookies".
EDIT 11/28/23: I was in Hewn again today and when I didn't see them, I asked about them. They said they are always available for pre-order, but they don't normally have them in stock for walk-ins. I guess I just lucked out a few days ago!
EDIT: I was in Hewn 12/1/23 and they have a holiday menu which includes a neapolitan cookie box among their Christmas items, for ordering online (
here) by Dec 20 for pickup Dec 23 or 24. This raises the possibility that these may be a seasonal item only available this time of year.