Old sieve for cook in the kitchen (7)
I believe the answer is:
griddle
'cook in the kitchen' is the definition.
'griddle' can be an answer for 'cook' (thesaurus). I'm unsure of the 'in the kitchen' bit.
'old sieve' is the wordplay.
'old' becomes 'g' (I can't justify this - if you can you should believe this answer much more).
'sieve' becomes 'riddle' (riddle is a kind of sieve).
'g'+'riddle'='GRIDDLE'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for griddle that I've seen before include "Iron plate for cooking on" , "Flat heated surface used for cooking" , "Is it a hot surface" , "cooking utensil" , "Heated metal cooking surface" .)