Caramelized Onion and Portobello Mushroom Soup with Goat Cheese Croutons

Name: Caramelized Onion and Portobello Mushroom Soup with Goat Cheese Croutons
Ingredients: 3 tablespoons butter; 1 1/2 pounds onions, halved, thinly sliced (about 5 cups); 4 fresh thyme sprigs; 1 1/2 pounds portobello mushrooms, stemmed, caps halved and cut crosswise into 1/4-inch-thick strips; 3 tablespoons Cognac or brandy; 3 garlic cloves, minced; 8 cups canned vegetable broth; 1 cup dry white wine; 18 1-inch-thick slices French-bread baguette, toasted; 8 ounces soft fresh goat cheese, room temperature