Flibber Flabber is a nasty green dietary food which is suppose to help someone lose weight, but you have to eat a ton of it to actually lose any weight.
Flibber Flabber appeared in the episode The Flibber Flabber Diet, when Truffles put everyone on a diet. Despite the fact that it supposed to help you lose weight, it's never actually seen doing so, while it was also shown to make Chowder fat (although this could be because Chowder eats in very large portions).
Flibber Flabber's also known for being "straight nasty" (according to Mung), which is likely a reason for the weight loss; however, Chowder thinks it's delicious. Flibber Flabber is produced from the mouth of the Flibbius Flabbius plant. Every time Mung Daal attempted to serve Truffles any kind of Flibber Flabber-themed meal, she'd spit it out on his face. Chowder, surprisingly, loved the Flibber Flabber, and was used as trash can to throw away the Flibber Flabber that Truffles didn't eat. This particular type of food seems to be and hugely resembles barf, as it was, and obviously, thrown up by a plant and the color green. Mung tried many ways to make the Flibber-Flabber taste better, but it really is straight nasty, as it still tasted awful:
Flibber Flabber smells of wet grass and sour yogurt, that's why Truffles did not like it. The Flibber Flabber made a cameo appearance in "Chowder's Catering Company".