śrī-śuka uvāca
hemante prathame māsi
nanda-vraja-kamārikāḥ
cerur haviṣyaḿ bhuñjānāḥ
kātyāyany-arcana-vratam
sri-sukah uvaca -- Sri Sukadeva Gosvami said; hemante -- during the winter; prathame -- in the first; masi -- month; nanda-vraja -- of the cowherd village of Nanda Maharaja; kumarikah -- the unmarried young girls; ceruh -- performed; havishyam -- unseasoned khichri; bhunjanah -- subsisting on; katyayani -- of the goddess Katyayani; arcana-vratam -- the vow of worship.
The word hemante refers to the month of Margasirsha -- from approximately the middle of November to the middle of December, according to the Western calendar. In Volume One, Chapter Twenty-two, of Krishna, the Supreme Personality of Godhead, Srila Prabhupada comments that the gopis "first ate havishyanna, a kind of food prepared by boiling together mung dal and rice without any spices or turmeric. According to Vedic injunction, this kind of food is recommended to purify the body before one enacts a ritualistic ceremony."