Shiva Purana
प्रविश्य मंडलं शंभोः पूजां पूर्ववदाचरेत् ॥ तत्राढकावरैस्सिद्धं तंदुलैः पायसं प्रभोः ॥ १३ ॥
After entering the circle, one should worship Lord Śiva as before. There the lord's payasam was prepared with rice cooked in adhakavars.
english translation
pravizya maMDalaM zaMbhoH pUjAM pUrvavadAcaret ॥ tatrADhakAvaraissiddhaM taMdulaiH pAyasaM prabhoH ॥ 13 ॥
hk transliteration by Sanscript