There's a lot of egg related stuff at the moment, I meant to make these layered bowls ages ago. You simply start with the base shape and then add rings around the outside until it reaches the desired height. I chose 15mm per ring, and the material is 2.7mm thick so 15 concentric rings provided a decent sized bowl. The bowl is made up from 2 layers with even layers all being concentric and odd layers all being concentric. I drew the maker lines into the middle so I knew how to line the layers up.
Once it was all glued together it became surprisingly sturdy. if I was doing more of these I would definitely investigate ways to make the bowl more curvy, perhaps slicing them with slic3r, but for now these are pretty cool. (svg here)