Bun batter; can be eaten but not whipped (10)
I believe the answer is:
unbeatable
'not whipped' is the definition.
The answer and definition are not the same part of speech. However, past participle verbs and adjectives occasionally mean the same thing.
'bun batter can be eaten' is the wordplay.
'batter' indicates anagramming the letters (I've seen 'battered' mean this).
'can be eaten' becomes 'eatable' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'bun' anagrammed gives 'unb'.
'unb'+'eatable'='UNBEATABLE'
'but' acts as a link.
Can you help me to learn more?
(Other definitions for unbeatable that I've seen before include "best" , "Invincible" .)