Sunan Ibn Majah, Book 29, Hadith 3389 (In-Book) ⓘ
It was narrated that ‘Umar bin Abu Salamah said: “The Prophet said to me, when I was eating: ‘Say the Name of Allah, the Glorified and Exalted.’”
حَدَّثَنَا مُحَمَّدُ بْنُ الصَّبَّاحِ، حَدَّثَنَا سُفْيَانُ، عَنْ هِشَامِ بْنِ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عُمَرَ بْنِ أَبِي سَلَمَةَ، قَالَ قَالَ لِيَ النَّبِيُّ ـ صلى الله عليه وسلم ـ وَأَنَا آكُلُ " سَمِّ اللَّهَ عَزَّ وَجَلَّ " .
also referenced under: Hadith 3265 (Reference) & Volume 4, Book 29, Hadith 3265 (DarusSalam)