Dessert maybe, something to chew on top performer’s tucked into (7)
I believe the answer is:
custard
'dessert maybe' is the definition.
'something to chew on top performer's tucked into' is the wordplay.
'something to chew on' becomes 'cud'.
'top performer' becomes 'star' (I've seen this before).
'tucked into' is an insertion indicator (I've seen this in other clues).
'cud' placed around 'star' is 'CUSTARD'.
(Other definitions for custard that I've seen before include "Dessert sauce" , "Pudding accompaniment" , "Type of apple" , "Yellow sauce" , "Cooked mixture of milk and eggs" .)