Try Amin's stuffing. It's the neatest! (7)
I believe the answer is:
tidiest
'the neatest' is the definition.
(I've seen this before)
'try amin's stuffing' is the wordplay.
'try' becomes 'test' (synonyms).
'amin' becomes 'idi' (I've seen this in other clues).
'stuffing' is an insertion indicator.
'test' placed around 'idi' is 'TIDIEST'.
'it's' acts as a link.
(Other definitions for tidiest that I've seen before include "smarter than anything" , "Neatest" , "One orderly more than others" , "most trim" , "optimally arranged" .)