There are few foods on the planet for which you expend more energy chewing it than you receive in calories. Raw celery is one of them. Konnayaku, the Japanese product made from a plant in the taro family called konnayku (also referred to as konjac or devil's tongue), is my low calorie food of choice. Here are some suggestions for how to cook with it, including a recipe for simmered konnyaku with beef.
'konnyaku' on Serious Eats
Konnyaku jellies are a wobbly, vegan treat made from the starchy root of the konjac plant, a yamlike tuber that’s also called devil's tongue, voodoo lily, snake palm, or elephant yam. When flavored with hijiki seaweed and sans sugar, konnyaku plays a laudable role in Japanese hotpots or oden.