The Two Festivals (Eids)

Bukhari :: Book 2 :: Volume 15 :: Hadith 73

Narrated Anas bin Malik,:

Allah's Apostle never proceeded (for the prayer) on the Day of 'Id-ul-Fitr unless he had eaten some dates. Anas also narrated: The Prophet used to eat odd number of dates.

Source materials are from the University of Southern California MSA site
Hadith eBooks converted from Imaan Star