Trifle with something sweet (4)
I believe the answer is:
fool
'trifle with' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for fool that I've seen before include "Jester or silly ass" , "Deceive" , "Ass - sweet" , "Trifle" , "Dimwit" .)