Shama-il Tirmidhi Chapter 025, Hadith Number 009 (151).
Anas bin Maalik Radiyallahu 'Anhu says: "Rasulullah Sallallahu 'Alayhi Wasallam loved gourd (dubbaa-dodhi-kadu). Once food - was presented to Rasulullah Sallallahu'Alayhi Wasallam or he attended an invitation. (The narrator doubts on which occasion this took place) where gourd was served. I knew Rasulullah Sallallahu'Alayhi Wasallam loved it. I searched for pieces from the curry and presented it to him".
We gather from this that if there are many things in a plate, then it is permissible to take a thing which one likes from the other side of the plate, provided the next person does not feel offended. The reason for searching for pieces of gourd is because it was the custom to have more gravy in the curry. Sayyidina Rasulullah Sallallahu 'Alayhi Wasallam also advised us to have more gravy in the curry so that the neighbours may also benefit.