Here's the premise: this is a cooking competition television show produced in the US. There are usually two parts to each episode, the first being a "mystery box" The mystery box contains several ingredients that the contestants cannot predict, and they are expected to use the ingredients in the box to cook a dish in a short period of time.
On this episode, one of the mystery box ingredients is fat choy (which translates roughly to hair vegetable), which the hosts call "black moss" and "chinese ground moss". This is not a moss, it is the terrestrial cyanobacterium Nostoc flagelliforme. Tune in around 5:30 to see the reactions of the contestants and judges to this ingredient. One contestant does well, all the while thinking that the Nostoc is some kind of noodle.