Carrot's nice in stew, throwing in turnip top and swede at the end (9)
I believe the answer is:
incentive
'carrot's' is the definition.
(I've seen this before)
'nice in stew throwing in turnip top and swede at the end' is the wordplay.
I cannot quite see how this works, but
an anagram of 'nice' is 'ince' which is located in the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is located in the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for incentive that I've seen before include "Something that motivates" , "Motivational reward" , "carrot" , "Payment to improve" , "A motivation" .)