The most common and most likely answer to this crossword clue is the 9 letter word PASTILLES
I've seen this crossword clue in The Guardian
P
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More clues leading to the result PASTILLES
Buddy explains!

The straight part
We know that "f/sweets" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case f/sweets = pastilles.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 PASTILLES mean?
PASTILLES noun- Any of several subdued tints of colors, usually associated with pink, peach, yellow, green, blue and lavender
- A drawing made with any of those colors.
- A type of dried paste used to make crayons.
- A crayon made from such a paste.
- Woad.
- A traditional dish in various Latin American countries, resembling a tamale, pasty, or calzone.
- A soft flavoured sweet/candy.
- A medicinal pill, originally compressed herbs. A throat pastille is a large candy-like lozenge, which, when sucked, releases oils to soothe a sore throat and sometimes vapors to help unblock the nose or sinuses.
- A small granular half-spheroid piece of material.
- A small cone of charcoal and aromatic substances, burned either as incense, or as a means of diffusing an agreeable odour.
- A paper tube containing a firework that causes a small wheel to rotate in burning.