Apple originally sandwiched in cream crackers and left as sweet (7)
I believe the answer is:
caramel
'sweet' is the definition.
(I know that caramel is a type of sweet)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for caramel that I've seen before include "Burnt sugar used for flavouring" , "Dark brown substance" , "Sugar solution heated till brown" , "Chewy sweet - burnt sugar" , "Toffee-like sweet" .)