Food served with bangers that is for old club (6)
I believe the answer is:
mashie
'is for old club' is the definition.
(obsolete golf club)
'food served with bangers' is the wordplay.
'food' becomes 'mash' (mashed potato).
'served with' says to put letters next to each other.
'bangers' becomes 'ie' (I am not sure about this - if you are sure you should believe this answer much more).
'mash'+'ie'='MASHIE'
'that' acts as a link.
Can you help me to learn more?
(Other definitions for mashie that I've seen before include "Old-fashioned golf club" , "Golf club for lofting" , "He aims (anag) - golfer's five iron, formerly" , "One of 9 [CLUBS]" , "Old golf club" .)