Sahih Bukhari Volume 3, Book 49, Hadith 2558

حَدَّثَنَا حَجَّاجُ بْنُ مِنْهَالٍ، حَدَّثَنَا شُعْبَةُ، قَالَ أَخْبَرَنِي مُحَمَّدُ بْنُ زِيَادٍ، سَمِعْتُ أَبَا هُرَيْرَةَ ـ رضى الله عنه ـ عَنِ النَّبِيِّ صلى الله عليه وسلم ‏"‏ إِذَا أَتَى أَحَدَكُمْ خَادِمُهُ بِطَعَامِهِ، فَإِنْ لَمْ يُجْلِسْهُ مَعَهُ، فَلْيُنَاوِلْهُ لُقْمَةً أَوْ لُقْمَتَيْنِ أَوْ أُكْلَةً أَوْ أُكْلَتَيْنِ، فَإِنَّهُ وَلِيَ عِلاَجَهُ ‏"‏‏.‏

Narrated By Abu Huraira : The Prophet said, "When your servant brings your meals to you then if he does not let him sit and share the meals, then he should at least give him a mouthful or two mouthfuls of that meal or a meal or two meals, as he has prepared it."