Mishkat al-Masabih
Anas said that God’s Messenger did not go out in the morning on the day of the breaking of the fast till he ate some dates, and he would eat an odd number. Bukhari transmitted it.
وَعَنْ أَنَسٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ لَا يَغْدُو يَوْمَ الْفِطْرِ حَتَّى يَأْكُلَ تَمَرَاتٍ وَيَأْكُلَهُنَّ وِتْرًا. رَوَاهُ الْبُخَارِيُّ
Reference