This is so sweet, darling! (5)
I believe the answer is:
honey
'darling' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for honey that I've seen before include "sweetener" , "Sweet product of insects" , "Produce of bees" , "sweet thing" , "Product of bees; darling" .)