The most common and most likely answer to this crossword clue is the 7 letter word FONDANT
I've seen this crossword clue in The Guardian
F
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N
D
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More clues leading to the result FONDANT
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The straight part
We know that "sweet" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sweet = fondant.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 FONDANT mean?
FONDANT noun- (usually uncountable) A flavored, creamy sugar preparation, used for icing cakes or as a base for candies.
- A candy filled with such a preparation.
- A sugar dough, usually prepared as large sheets (rolled fondant), used in place of icing to cover large areas of cakes, composed of sugar, water, gelatin, glycerine.
- (usually uncountable) Fondue.
- (usually uncountable) The base or flux, in enamel, which is colored throughout by metallic oxide while in a state of fusion.
- Stooping, as for prey: said of an eagle, a falcon, etc.