Nutritional Yeast is a "deactivated" yeast. Meaning it doesn't rise like bread yeast. Because the name is so not good sounding, I've picked up the slang term of "Nooch". I think this is the best description of it that I could find: nutritional yeast, believe it or not, is a valuable nutritional supplement as it contains high levels of protein and vitamins. Nutritional yeast is a non-active form of yeast that you can use in a number of ways in the kitchen and it adds a delicious nutty, cheesy flavor. Add it to salads, casseroles, soups, popcorn, crackers and dips to experience all of its great health benefits."
(Read more: How to Benefit From Nutritional Yeast | eHow.com http://www.ehow.com/how_4454257_benefit-from-nutritional-yeast.html#ixzz1g3T6svRd)

I have to tell you, it took me a long time to finally buy some to try. I couldn't fathom anything called "nutritional yeast" tasting good. I finally gave in and after some research purchased "KAL - Yeast Flakes" from Amazon.com. Oh....my....goodness!! This stuff is like crack! LOL I put it on everything! I make plain pasta with some Earth Balance margarine and add some nooch! Also, on air popped popcorn, spritzed with olive oil and then sprinkle on the nooch and roast veggies, some cooking spray and then...you guessed it...sprinkle on the yeast! YUMMY!!! It has a slight cheesy or nutty flavor. I have not tried eating it alone, like I think you can mix it with water and drink it as a broth, but I haven't tried that. But I really do add it to everything. I use it like you would a Parmesan cheese I guess. In any case, I tell everyone about it! I love the stuff and keep it in large quantities in my house!

Good question. I bought some the other day for my first time. Unfortunately I am working 12 hour shifts all weekend long so I can't try any of my new recipes. I will let you know what I think.

So delish! Jae Steele has some yummy recipes to make cheese sauce.

I am addicted to air popped popcorn with nooch and earth balance buttery spread. So yum!