Defrosts what’s been cooked (5)
I believe the answer is:
thaws
'defrosts' is the definition.
The answer and definition can be both related to change as well as being verbs in their -s form.
Maybe they are linked in a way I don't understand?
'what's been cooked' is the wordplay.
'what's' can be anagrammed to 'THAWS'.
However, I am not clear how this is indicated.
Can you help me to learn more?
(Other definitions for thaws that I've seen before include "Starts to unfreeze" , "(Of snow) melts" , "friendlier times?" , "As role of Morse was to become" .)