I am told cream crackers can be sensational (12)
I believe the answer is:
melodramatic
'sensational' is the definition.
(I've seen this before)
'i am told cream crackers' is the wordplay.
'crackers' indicates an anagram (informal term for mad).
'i'+'am'+'told'+'cream'='iamtoldcream'
'iamtoldcream' with letters rearranged gives 'MELODRAMATIC'.
'can be' acts as a link.
(Other definitions for melodramatic that I've seen before include "like ham?" , "Exaggerated - over-emotional" , "Sensational" , "Emotionally overblown (in theatre)" .)