Cream brilliant in cheese's centre (5)
I believe the answer is:
elite
'cream' is the definition.
(as in the cream of the crop)
'brilliant in cheese's centre' is the wordplay.
'brilliant' becomes 'lit' (brilliant can mean shining or lit up).
'in' is an insertion indicator.
'cheese's' becomes 'wheel's' (wheel can mean a circular cheese).
'centre' indicates the central letters.
The middle letters of 'wheels' are 'ee'.
'lit' inserted into 'ee' is 'ELITE'.
(Other definitions for elite that I've seen before include "Select body, cream" , "Superior group in society" , "Superior or favoured group of people" , "Best, privileged, group" , "A privileged or superior social group" .)