Another quick tip if you have no food at all, not even enough to make a stew, is to play on pause.
By that I mean, keep the game paused while you search out mushrooms. This way you will be able to get enough mushrooms to make a stew without losing any of your villagers. Or even if you don't have enough tech yet to make stew, it will be enough to keep you going until the crops are ready. It will make your game a bit boring for an hour or so, but at least you'll be able to save your villagers.