Be of use and dish up (5)
I believe the answer is:
serve
I believe this clue is a double definition.
'be of use' is the first definition.
(I've seen this before)
'dish up' is the second definition.
('serve' can be a synonym of 'dish up')
'and' is the link.
(Other definitions for serve that I've seen before include "Bring food to table" , "Put the tennis ball in play" , "Offer up" , "Start a tennis match" , "Perform duties for" .)