It is stated that Goddess Parvati took the form of Angala Amman to help Shiva rid of the Kapala that was following Him after He cut off the fifth head of Brahma.
Legend has it that Shiva took the form of Bhairava and cut off the fifth head of Brahma for being arrogant about His creation.
On advice of Vishnu, she prepared food for Shiva at Thandakarunyam Tirth near Angikula Tirtham.
Goddess Parvati intentionally scattered food around the place and Kapala came down to eat them leaving the hand of Shiva.
Goddess Parvati seized this opportunity and took the fierce form of Angalamman and stamped down the Kapala using her right leg.