The Messenger of Allah ﷺ said, "When food is placed before you, do not eat from its center, for blessing descends upon its center. Rather, eat from its sides."
حدثنا عمر بن عبيد عن عطاء بن السائب قال دعينا إلى طعام وفينا سعيد بن جبير ومقسم مولى ابن عباس فلما وضع الطعام قال سعيد كلكم بلغه ما قيل في الطعام قال مقسم حدث يا أبا عبد الله من لم يكن يسمع فقال
قال رسول الله ﷺ إذا وضع الطعام فلا تأكلوا من وسطه فإن البركة تنزل وسطه وكلوا من حافتيه أو حافتيها
Its chain is at least hasan. I have not found anything indicating that Amr bin Ubayd Tanafisi heard from Ata bin Saaib before the latter's memory became confused, and it appears to me that he was one of those who heard from him at a later stage.Hakim (4:16) narrated it in similar fashion through Humaydi, from Sufyan, from Ata. We have already pointed to his narration at 2439, and see also 3213, 3190, and 2730.