How to Make It
Heat oil in a saucepan over medium heat. Add onion to pan; cook 4 minutes or until tender (do not brown), stirring frequently. Add mustard seeds and pepper; cook 1 minute. Stir in juice and remaining ingredients; bring to a boil. Cover, reduce heat, and simmer 15 minutes. Uncover; cook an additional 5 minutes or until liquid almost evaporates.