I made a neat shape yesterday called a humybug. I'd never done one before. Followed the tutorial here: https://plushcat.blogspot.com/p/humbug-tutorial.html. You start with a rectangle and sew it into a little tetra shape. It's cute. I think it would make a good cat toy. :)
Cool! Post a picture if you make one. It's a little fiddly at the end, but fun and quick to make.
I used a random scrap of some terrible thick stuff from joann's. My advice would be to use a thinner piece of Aida or evenweave, or make a bigger rectangle. The corners were really difficult to squish shut.
I like it, the specific pattern you picked reminds me of a Sierpinsky triangle. I was wondering why it's called a humbug since that is a commonly used word where I'm currently located, but given that the article displays it as a Christmas ornament, I'd speculate it's based on Ebenezer Scrooge's use of the word in A Christmas Caroleven though that's not the origin of the word.
I was thinking closest food item would be Onigiri, but you're right! I was only able to find a Swedish product picture, but these definitely existed. Now I feel old ;)