Combine porcini mushrooms and boiling water in a small bowl, let stand 15-20 minutes or until tender.

Heat oil in large saucepan over medium heat. Add onions; cook 5 minutes or until transparent, stirring occasionally. Add crimini mushrooms, garlic and thyme; cook 8 minutes, stirring occasionally. Add flour; cook and stir 1 minute. Stir in broth.

Drain porcini mushrooms, reserving liquid. Chop mushrooms; add mushrooms and reserved liquid to saucepan. Bring to a boil over high heat. Reduce heat; simmer 10 minutes. Stir in cream, wine, if desired, and pepper. Simmer 5 minutes or until heated through. Serve immediately.