In this week's Rachael Ray's Kids Cook-Off immunity challenge, the remaining contestants could use only five ingredients (not counting salt) to make a sauce for a pasta dish. This is no easy task, but the kids did a great job, especially Scarlett, who won with her earthy mushroom pasta.

But there's one secret (and free) ingredient we didn't see in any of the dishes and that's the pasta cooking water! Just a little of this starchy and salty water can be a real lifesaver. Cooked noodles tend to suck up a ton of sauce, leaving pasta dishes dry. A splash of this magic water can help loosen the sauce up, plus add plenty of body (thanks to the starch) and seasoning, if you salted your water (which we suggest you do). We've saved literally hundreds of gloopy pasta dishes in our test kitchen with pasta water — it works like a charm!

Check out our spaghetti with marinara: A little pasta water saved the day.

There are only a few contestants left; tune in Monday at 8|7c to watch the competition continue.