Fra Angelico

This one's round — a tondo — and from what I can find, historians don't fully agree who painted most of it: it's catalogued under one name, but they think a second painter, plus workshop hands, did a lot of the actual work. It's been called the 'Cook Tondo' for decades, after a private collector, even though it left his collection a long time ago.

This is one of nine little panels that used to sit along the bottom of a much bigger altarpiece, for a church called San Marco — they've ended up scattered across different museums since, from what I can find: one in Paris, a few in Munich. The story behind it: a woman named Palladia was healed by these two brothers and tried to thank one of them with a gift, which apparently started an argument between the saints over whether it was okay to accept it.