Process chiles and salt in a food processor about 30 seconds or until minced, stopping to scrape down sides as needed. Transfer chile mixture to a sterilized 1-qt. glass jar. Cover with cheesecloth, and let stand in a cool, dry place 2 days.
Remove cheesecloth, and stir in vinegar. Cover mixture with cheesecloth, and let stand in a cool, dry place 5 days. (Skim and discard any film from surface, if necessary.) Cover jar with a tight-fitting lid; refrigerate up to 6 months.