Uovo in Raviolo

This was buried in a reply to yet another useless troll but I think it deserves a mention:
A friend across the hall at the office brought something for lunch I'd never heard of before.  (His wife is an excellent cook.) Ravioli filled with ricotta cheese and an egg yolk that stays runny even after the ravioli is cooked in boiling water and then plated with a sauce.  This recipe I found online calls for pancetta in the sauce but she makes a brown butter sauce.  He reheated it gently on medium setting in the microwave so that the egg yolk was still runny when he cut into the Uovo in Raviolo.
https://www.seriouseats.com/uovo-in-raviolo-runny-egg-yolk-ravioli-ricotta-recipe
He says it's very labor intensive dish so she doesn't prepare it very often.
Jill