Green Bean Bake Revisited

1. In a large skillet cook onions, covered, in hot oil over medium-low heat for 13 to 15 minutes or until onions are tender. Uncover; add brown sugar. Cook and stir over medium-high heat for 3 to 5 minutes or until onions are golden and caramelized. Cool slightly; transfer to a storage container. Cover and chill up to 24 hours.

2. In a Dutch oven cook green beans, covered, in a small amount of boiling water for 4 minutes. Drain. In a 3-quart au gratin or baking dish combine green beans and mushrooms. Cool slightly; cover and chill up to 24 hours.

3. Let onions and bean mixture sit at room temperature for 30 minutes. Combine olive oil, soy sauce, and balsamic vinegar. Pour over vegetables, tossing to coat. Preheat oven to 400 degrees F. Roast beans, uncovered, for 30 minutes, stirring once until crisp tender. Meanwhile, in a medium mixing bowl beat together cheese and milk with an electric mixer on medium speed.

4. Spoon cheese in lengthwise mounds along center of baking dish. Top with caramelized onions. Return to oven; heat 5 to 8 minutes or until cheese and onions are heated through.