Mirepoix means onions, celery and carrots finely diced and gently cooked in butter or olive oil until soft but not brown, used as a base for many savoury French dishes. Often ham is added to meaty dishes. If the desired sauce is white, as in a blanquette de veau, parsnips may replace the carrots. Other dishes might ask for a different mix of vegetables.
It takes its name from the otherwise forgettable Charles-Pierre-Gaston François de Lévis, Duc de Lévis-Mirepoix (1699–1757), French field marshal and ambassador from Mirepoix who could afford to have a good chef because Louis XV was very fond of his wife. And it was this excellent but anonymous chef who standardized the technique.
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