Though it sounds like it should be a slick-looking fudge or perhaps a very bad piece of candy, chocolate tube slime is neither of those things. It is not even a fungus. Heck, it doesn't even have a chocolate color at first. (You can see one changing colors in the time-lapse above.)
Slime mold is a common name for more than 900 different species, including chocolate tube slime (Stemonitis fusca). Starting as a white-ish bundle of plasmodia, chocolate tube slime eventually develops hair-like sporing stalks with sporangia at the top. This sporangia contains the spores. It's more dusty than slimy. Spores of Stemonitis fusca are scattered through the dust so that the species can thrive.
Like most slime molds, chocolate tube slime can be found growing on rotting wood just anywhere in the world, from Maine to New Zealand. Despite its vaguely chocolatey appearance, it's probably best not to eat these odd-looking stalks. The plasmodia, however, are good snacks for slugs.
Take a look.