Abu Dawud Book 1, Hadith Number 191.
Chapter : The performing of ablution is not essential when one takes something cooked with the help of fire.
Narated By Muhammad b. al-Munkadir : I heard Jabir b. ‘Abd Allah say : I presented bread and meat to the Prophet (may peace be upon him). He ate them and called for ablution water. He performed ablution and offered the noon (zuhr) prayer. He then called for the remaining food and ate it. He then got up and prayed and did not perform ablution.