Added zest in the kitchen (6)
I believe the answer is:
spiced
'added' is the definition.
Although both the answer and definition are past participle verbs, I can't understand how one could define the other.
'zest in the kitchen' is the wordplay.
'zest' becomes 'spice' (I've seen this in another clue).
'in the kitchen' becomes 'd' (I am not sure about this - if you are sure you should believe this answer much more).
'spice'+'d'='SPICED'
Can you help me to learn more?
(Other definitions for spiced that I've seen before include "Flavoured with, eg, mace" , "was over-scrupulous" , "Seasoned with aromatic ingredients" , "Highly flavoured" , "Given more flavour" .)