Cook's good sieve (7)
I believe the answer is:
griddle
'cook's' is the definition.
(thesaurus)
'good sieve' is the wordplay.
'good' becomes 'g' (abbreviation).
'sieve' becomes 'riddle' (riddle is a kind of sieve).
'g'+'riddle'='GRIDDLE'
(Other definitions for griddle that I've seen before include "Iron plate for cooking on" , "cooking utensil" , "Cook" , "Heated metal cooking surface" , "Is it a hot surface" .)