A 3D scanned onion.

There are 3 files attached. The files are pretty big because it's literally untouched.

Onion-Scan-Mesh.stl is the main file, printable but you do need to make the bottom flat yourself.
Onion-Scan-Mesh-Flat-Bottom.stl has a flat bottom so you can print it right away.
Onion-Scan-Textured.obj is the textured onion (as seen on one of the screenshots).