sof·frit·to 
(sō-frētō, sə-)
(sō-frētō, sə-)n. pl. sof·frit·tos
A mixture of seasonings and finely chopped vegetables, such as onions, garlic, and celery, that is sautéed in olive oil and used as a base for many Italian dishes.
[Italian, past participle of soffriggere, to brown, from Vulgar Latin *suffrīgere, to fry lightly; see SOFRITO.]