Ten fancy cake topping - it's tempting (8)
I believe the answer is:
enticing
'tempting' is the definition.
('entice' can be a synonym of 'tempt')
'ten fancy cake topping' is the wordplay.
'fancy' indicates an anagram.
'cake topping' becomes 'icing' (I've seen this before).
'ten' anagrammed gives 'ent'.
'ent'+'icing'='ENTICING'
'it's' acts as a link.
(Other definitions for enticing that I've seen before include "Having an allure" , "Attractive" , "Luring" , "Alluring" , "Attracting by offering pleasure" .)