Comes from the title of a jpeg file found on google image search entitled, "frydabing." It is literally referring to frying a chinese oil cake (bing). It means "to do good," or can be used as an exclamation or an insult.
Everything on this page with regards to origin is BS. This word is a latin phrase, therefore it is as Italian as it is Spanish. I have known this expression since I was a kid and it is used in Spanish very very often, same goes for "Forget about it"