Smell's back, is anyone cooking with onions? (9)

I believe the answer is:

lyonnaise

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'cooking with onions?' is the definition.
(I've seen this before)

I can't explain the remainder of the clue.

(Other definitions for lyonnaise that I've seen before include "cooking with onions" , "cooked in a way to make you cry?" , "Served with onions" , "(Of potatoes) cooked with onions in a wine sauce" .)

I've seen this clue in The Independent.

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