À la Lyonnaise is a French cooking term used to describe a dish that uses onions in some way. “À la Lyonnaise” means in the style of Lyons, France.

In the grande cuisine sense, it means either a side accompaniment of onions that are stuffed and braised, plus potatoes, or garnished with chopped onions that have been sautéed in butter, then had a bit of vinegar and chopped parsley stirred into them.

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