Musnad Ahmad 30:2779

Muhammad ibn Ja'far narrated to us, he said: Shu'bah narrated to us, from Abu Bakr ibn Hafs, he said: I heard al-Agharr, he said: I heard Abu Hurairah narrating from the Messenger of Allah, may Allah bless him and grant him peace, that he said: "Perform ablution from what the fire has cooked."