Cook book coming before increase in salary (6)
I believe the answer is:
braise
'cook' is the definition.
(braising is a kind of cooking)
'book coming before increase in salary' is the wordplay.
'book' becomes 'b'.
'coming before' is a charade indicator (letters next to each other).
'increase in salary' becomes 'raise' (I've seen this before).
'b'+'raise'='BRAISE'
(Other definitions for braise that I've seen before include "Cook slowly with little liquid in closed container" , "Re bias (anag.)" , "Fry and then stew (food)" , "Fry then stew slowly" , "Cook or stew slowly" .)