Mirepoix

Mirepoix is a French aromatic garnish composed of regular dice of carrot, onion, celery stalk and sometimes leek, cut to one centimetre per side for stock preparations, or more finely (matignon or brunoise) for sauces. The name honours the Marshal of Mirepoix in the 18th century. Mirepoix is sweated in butter or oil before deglazing, which develops sugars and fixes aromas. A well-managed mirepoix constitutes the aromatic foundation of brown and white stocks, an essential stage in all French three star kitchens (Source: Auguste Escoffier, Le Guide culinaire, 1903).