Enthusiast served up perfect example of spice (6)
I believe the answer is:
nutmeg
'spice' is the definition.
(nutmeg is a kind of spice)
'enthusiast served up perfect example' is the wordplay.
'enthusiast' becomes 'nut' (I've seen this before).
'served up' shows that the letters should be reversed in order.
'perfect example' becomes 'gem'.
'gem' reversed gives 'meg'.
'nut'+'meg'='NUTMEG'
'of' is the link.
(Other definitions for nutmeg that I've seen before include "put the ball through" , "Kick the football between an opponent's legs" , "Kernel and girl for a spice" , "Fragrant tropical seed ground as spice" , "Give out light" .)