Occasionally leftovers do not make it into the fridge, and you need to know if it's still safe to eat. This guide is about food left out overnight.
The stew in my slow-cooker was just finishing cooking when I went to bed at 10:00 pm. It was way too hot to put in the refrigerator. I left it covered on the counter and refrigerated it at 7:30 in the morning. Is it still OK to eat?
Yes, it is fine to eat. I do this all the time.
If the house is cool & not hot it's ok to eat.
Next time put it right into the fridge-doesn't matter that its hot. If the crock is removeable, just put a folded towel under if if your fridge shelves are glass. Uncover it to facilitate cooling. The reason people used to cool things before putting them in the icebox was that hot things would melt the ice. With a fridge its not an issue.
The FDA says food should not be eaten if left out after two hours. I don't adhere to this strictly but all night, I wouldn't chance it.