• 2 tablespoons parve margarine 
•  2 medium red onions (about 1 pound), each cut into 4 wedges, then thinly sliced crosswise
•  1 bag (12 ounces) cranberries (3 cups)

•  3/4 cup packed light brown sugar
•  2 tablespoons balsamic vinegar
•  1/4 teaspoon salt

1. In nonstick 12-inch skillet, melt margarine over medium heat. Add onions, and cook 15 to 20 minutes or until onions are dark brown and tender, stirring occasionally.
2. Increase heat to medium-high. Stir in cranberries, sugar, vinegar, salt, and 1 cup water; heat to boiling. Reduce heat to medium and cook, uncovered, 12 to 15 minutes or until most cranberries pop and mixture thickens slightly, stirring occasionally. Spoon sauce into serving bowl; cover and refrigerate until well chilled, at least 3 hours.

Sauce can be made up to 4 days ahead and stored, covered, in the refrigerator.