Can anyone provide me the verse which indicates Maa Parvati as supreme Goddess?
Yes Devi Bhagvatam mentions so -
9-73. The Devas said :-- “O Auspicious One! Thou art the only Cause of this Illusion of this world, presenting an unreal appearance. So Thou art the Lady of all the beings. So, Obeisance to Thee, the S’âkambharî! Hundred-eyed! O Auspicious One! Thou art sung in all the Upanisadas; The Destroyer of the Durgama Asura! We bow down to Thee, the Lord of Mâyâ, the Dweller in the five sheaths Anna, Rasa, etc. We meditate upon Thee, the Lady of the universe, as demonstrated by Pranava Aum, whom the chief Munis meditate with their Nirvikalpa hearts. Thou art the Mother of the endless crores of universe! Thou assumest the Divine Bodies at times for our welfare! Thou art the Mother of Brahmâ, Visnu and others; we bow down to Thee with all our heart.
The above was said for Parvati you can find the entire things here - https://www.sacred-texts.com/hin/db/bk07ch28.htm
In Mahabharata Devi Durga was called as supereme goddess and greater than all deities by Vaishampayan and Yudhishthira.
he began to praise mentally the Divine Durga, the Supreme Goddess of the Universe, born on the womb of Yasoda, and fond of the boons bestowed on her by Narayana, sprung from the race of cowherd Nanda, and the giver of prosperity,
It is for this, O you that hast slain the Mahishasura, that you are praised and worshipped by the gods for the protection of the three worlds. O you foremost of all deities, extend to me your grace, show me your mercy, and be you the source of blessings to me.