Has a tangy, vibrant taste. Is dark green in color. Can be found at your local Rosauers, if you ask for it specifically.
In 1986 there was controversy as to whether it should be banned in several European countries due to mild hallucinogenic properties. However the scientists had confused clackle sauce with an unrelated substance by the same name and interest in the sauce eventually subsided. Clackle sauce remains legal throughout Europe.
It is also a main ingredient in many whole wheat breads.