The most common and most likely answer to this crossword clue is the 9 letter word BRASSERIE
I've seen this crossword clue in The Times
B
R
A
S
S
E
R
I
E
More clues leading to the result BRASSERIE
- Item of clothing I put down in restaurant
- Supporters mostly run restaurant
- Clothing I adjusted for restaurant
- Place to get a bite from fish around river by lake
- Restaurant with fish — about right by lake above Niagara
- Piece of clothing I misplaced in this eating place
- French food about right, while service vacuous in restaurant
- A place to eat for senior officers by a lake
- Queen admitted to old club where cheap food served
- Club entertains queen in restaurant
Buddy explains!

The straight part
We know that "Restaurant" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case restaurant = brasserie.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 BRASSERIE mean?
BRASSERIE noun- A small, informal restaurant that serves beer and wine as well as simple food