I recently ordered chirashi at a place where I had gotten sushi (but not chirashi) several times before. When it came, it was--as expected--a lovely lacquered box filled with an assortment of sashimi over seasoned rice, with oshinko, seaweed, shiso leaf, shoestring daikon and other little nibbles. Unlike other times I've ordered chirashi elsewhere, this time I was also given an extra octagonal plate, flat except that the points curled up toward the ceiling. The plate was approximately 6" wide and completely empty. To me, it looked like an upside-down trivet.
I've searched on the web but I can't find a picture of a similar plate and I can't figure out what I was supposed to use it for. At the time I just ignored it, but next time I'd like to know what to do with it.
Does anyone know what this dish is for? Thanks!