soffritto

noun

1. (countable, uncountable)A fried mixture of chopped onions, carrots and celery, used as the beginning point of a dish, especially in Italian cuisine; may also contain garlic, shallot, and leek.

   “Most European cultures use a patiently chopped, heated and stirred vegetable mixture, such as a mirepoix or soffritto, always including members of the onion family, and Pollan explores the chemistry of these, as well as their adaptive value.”