I was a boy under the care of Messenger of Allah ﷺ and my hand used to go around the dish while I was eating. So Messenger of Allah ﷺ said to me, 'O boy! Mention the Name of Allah and eat with your right hand, and eat of the dish what is nearer to you." Since then I have applied those instructions when eating.  

أَنَّهُ سَمِعَ عُمَرَ بْنَ أَبِي سَلَمَةَ يَقُولُ كُنْتُ غُلاَمًا فِي حَجْرِ رَسُولِ اللَّهِ ﷺ وَكَانَتْ يَدِي تَطِيشُ فِي الصَّحْفَةِ فَقَالَ لِي رَسُولُ اللَّهِ ﷺ يَا غُلاَمُ سَمِّ اللَّهَ وَكُلْ بِيَمِينِكَ وَكُلْ مِمَّا يَلِيكَ فَمَا زَالَتْ تِلْكَ طِعْمَتِي بَعْدُ