Buffet with bagel or relish (5)
I believe the answer is:
gusto
'relish' is the definition.
(I know that relish can be written as gusto)
'buffet with bagel' is the wordplay.
'buffet' becomes 'gust' (buffet can mean a gust of wind).
'with' means one lot of letters go next to another.
'bagel' becomes 'O' (bagel can mean a score of zero in tennis).
'gust'+'o'='GUSTO'
'or' is the link.
(Other definitions for gusto that I've seen before include "Zest, zeal" , "Verve, zest" , "Got us with great enjoyment" , "ardour" , "Great enjoyment in doing something" .)