Taste one in the dish (6)
I believe the answer is:
palate
'taste' is the definition.
(palate can mean an ability to distinguish tastes)
'one in the dish' is the wordplay.
'one' becomes 'la' (I can't explain this - if you can you should give a lot more credence to this answer).
'in the' is an insertion indicator.
'dish' becomes 'pate' (I've seen this in other clues).
'la' put within 'pate' is 'PALATE'.
Can you help me to learn more?
(Other definitions for palate that I've seen before include "Liking" , "Roof of the mouth, seat of taste" , "One may savour" , "Sense of taste at roof of mouth" , "relish" .)