The most common and most likely answer to this crossword clue is the 13 letter word CONFECTIONERY
I've seen this crossword clue in The Times
C
O
N
F
E
C
T
I
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R
Y
Buddy explains!
The straight part
We know that "sweets" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sweets = confectionery.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CONFECTIONERY mean?
CONFECTIONERY noun- Foodstuffs that taste very sweet, taken as a group; candies, sweetmeats and confections collectively.
- The business or occupation of manufacturing confectionery; the skill or work of a confectioner.
- A store where confectionery is sold; a confectioner's shop.