Poison found in any iced confection (7)
I believe the answer is:
'poison' is the definition.
(cyanide is poisonous)
'any iced confection' is the wordplay.
'confection' indicates an anagram (I've seen this in other clues).
'anyiced' with letters rearranged gives 'CYANIDE'.
'found in' acts as a link.
(Other definitions for cyanide that I've seen before include "Toxic salt" , "Nice day (anag) - poison" , "Poisonous compound" , "Highly toxic substance" , "killer" .)