Keep this rich condiment in the refrigerator for nights when you need to elevate simply roasted chicken, steak, or fish.
In a medium pot, heat oil overmedium heat and cook onions,covered, stirring occasionally untiltranslucent, about 15 minutes.Add water, vinegar, and sugarand cook uncovered, stirring, untilonions are caramelized, about30 minutes more. Season withsalt. Let cool completely.
Onion jam can be refrigerated for up to 2 weeks.