The most common and most likely answer to this crossword clue is the 9 letter word LYONNAISE
L
Y
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N
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More clues leading to the result LYONNAISE
- Snail one Yankee cooked with onions
- Poor snail one Yankee cooked with onions
- One way to do spuds when cooking online, say?
- In NY a sole freshly cooked with onions
- Of oniony meals, first of all cut, then cooked
- Polynesians peeled bananas to be served with onions
- Cook only in a case of sauce with onions
- In New York, a sole cooked with onions
- Could be online, say, from a French city
- Cooked with onions only, as in the final mix
Buddy explains!

The straight part
We know that "with onions" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case with onions = lyonnaise.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 LYONNAISE mean?
LYONNAISE adjective- Of or from Lyons
- Cooked with onions, especially caramelized onions.
- Prepared in a style typical to Lyons.