I love happy accidents. Like, say, when you're all set on making beef stew, and have purchased all the ingredients and even begun the cooking process. And then discover that you've forgotten one of the key ingredients...but then the ingredient you end up swapping in makes it miles and miles better.
I'm talking about beef stew made with - yes - chicken stock. I know what you're thinking: That will taste like chicken soup. If I wanted chicken soup, I would make chicken soup.