Menu as set must include starter of bass or ray (7)
I believe the answer is:
sunbeam
'ray' is the definition.
(sunbeam is a kind of ray)
'menu as set must include starter of bass' is the wordplay.
'set' indicates an anagram (instruction to set the letters).
'must include' is an insertion indicator.
'starter of' indicates taking the first letters.
The first letter of 'bass' is 'b'.
'menu'+'as'='menuas'
'menuas' is an anagram of 'suneam'.
'suneam' placed around 'b' is 'SUNBEAM'.
'or' is the link.
(Other definitions for sunbeam that I've seen before include "Ray of natural light" , "Bright ray -- bus name (anag)" , "Ray of solar light" , "sheds a bit of light" , "Bright shaft of daylight" .)