Skin colour switched with zest (5,4)
I believe the answer is:
lemon peel
'zest' is the definition.
(I've seen this before)
'skin colour switched' is the wordplay.
I cannot really understand how this works, but
'skin' could be 'peel' (synonyms) and 'peel' is present in the answer.
'colour' could be 'lemon' (lemon is a kind of colour) and 'lemon' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
'with' acts as a link.
Can you help me to learn more?
(Other definitions for lemon peel that I've seen before include "Source of zest" , "twist" .)