Bit around fine, first-rate dessert (7)
I believe the answer is:
parfait
'dessert' is the definition.
(parfait is a kind of dessert)
'bit around fine first-rate' is the wordplay.
'bit' becomes 'part' (I've seen this in other clues**).
'around' indicates putting letters inside.
'fine' becomes 'f' (abbreviation).
'first-rate' becomes 'ai' (resembles Ap, informal term for excellent).
'f'+'ai'='fai'
'part' going around 'fai' is 'PARFAIT'.
(Other definitions for parfait that I've seen before include "Escoffier's faultless" , "Fruit and cream dessert" , "sweet" , "Rich iced pudding of eggs and cream." , "Rich dessert" .)