The most common and most likely answer to this crossword clue is the 9 letter word CAFETERIA
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More clues leading to the result CAFETERIA
- There's scoffing here, with Conservative Party breaking into song
- Fund-raiser in vehicle, one by a restaurant
- Accountant at fair gets wind up, needing place to eat
- What serves diners a feta-rice mix?
- Cliff top, with a fair easterly breeze, as a place to eat?
- A fair demeanour returns after cold nosh here
- Diner‘s companion’s first to celebrate, bursting into song
- Ace fare it cooked?
- Order ice after a place to eat is found
- About to attend a function before retrospective show in restaurant
Buddy explains!

The straight part
We know that "What serves diners" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case what serves diners = cafeteria.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 CAFETERIA mean?
CAFETERIA noun- A restaurant in which customers select their food at a counter then carry it on a tray to a table to eat
- A dining area in an institution where meals may be purchased (as above), provided, or brought in from elsewhere