The most common and most likely answer to this crossword clue is the 6 plus 7 letter word BELLES LETTRES
I've seen this crossword clue in The Guardian
B
E
L
L
E
S
L
E
T
T
R
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S
More clues leading to the result BELLES LETTRES
Buddy explains!

The straight part
We know that "fine writing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case fine writing = belles lettres.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 BELLES LETTRES mean?
BELLES LETTRES noun- The humanities.
- Literature, particularly light compositions valued for their aesthetic properties.
- Literary studies, particularly literary aesthetics.