This is rare, but when pole vault athletes break their pole, they always snap in more than two pieces, e.g., https://www.youtube.com/watch?v=1yCnPgD4YZg

In 2005, two french researchers Sebastien Neukirch and Basile Audoly explained in a PRL paper that when you bend a spaghetti stick, a vibration wave sets off from the top of the curved spaghetti throughout the rest of the stick. This “snap-back” vibration leads to the fragmentations. They later even won an Ig Nobel Prize in Physics in 2006.

In 2018, a group of researchers at MIT reported in PNAS that, by twisting the spaghetti stick really hard while bending it, one can break the stick in two halves.

I tried many times to test out the twist+bending approach in my kitchen but never succeeded to snap a spaghetti stick in half. It always snaps into at least 3 pieces. Did anyone get luck?