Cook up a new diet! (4)
I believe the answer is:
edit
'cook up' is the definition.
Although both the answer and definition are verbs in their base form, I don't understand how they can define each other.
'a new diet' is the wordplay.
'a new' indicates an anagram.
'diet' anagrammed gives 'EDIT'.
Can you help me to learn more?
(Other definitions for edit that I've seen before include "What our boss does" , "Censor" , "Redact, perhaps" , "Alter text" , "Emend" .)