Gathered sandwich condiment, you might say (8)
I believe the answer is:
mustered
'gathered sandwich' is the definition.
'mustered' can be an answer for 'gathered' (mustering is a kind of gathering). I am unsure of the 'sandwich' bit.
'condiment you might say' is the wordplay.
'condiment' becomes 'mustard' (mustard is a kind of condiment).
'you might say' shows a homophone (sound like).
'mustard' sounds like 'MUSTERED'.
Can you help me to learn more?
(Other definitions for mustered that I've seen before include "Caused to assemble" , "Assembled, gathered together - say troops" , "Marshalled" , "Brought together" .)