Add margarine and onions to skillet; cook on medium heat 5 min. or until onions are crisp-tender, stirring occasionally. Stir in mushrooms, bay leaves and thyme; cook 10 min., stirring occasionally. Add broth; bring to boil. Simmer on low heat 3 min. or until slightly thickened. Add cream cheese product; cook until melted, stirring frequently. Remove and discard bay leaves.