Pho garnish (5)
I believe the answer is:
basil
'pho garnish' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for basil that I've seen before include "serially chaotic character" , "Culinary plant" , "Fragrant herb" , "Fellow" , "Herb (from Fawlty Towers?)" .)