Musnad Abu Ya'la al-Mawsili 113:6

Abbas ibn al-Walid al-Narsi narrated to us, Wahib narrated to us, from Ayyub, from Abu Qilabah, from Anas, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "When dinner is served and the prayer is established, begin with dinner."