French Onion Soup

1/4 cup (60 mL) unsalted butter

3 each large onions, thinly sliced

2 dried bay leaf

1/2 tsp (3 mL) fresh thyme leaves, chopped

2 tbsp (30 mL) all-purpose flour

1/2 cup (125 mL) red wine

1 tbsp (15 mL) balsamic vinegar

1 carton (900 mL) CAMPBELL’S® Ready to Use Beef Broth

1/2 tsp (3 mL) black pepper

1 French baguette, 1/2” bread slices, toasted

1/2 lb (227 g) Gruyère cheese, shredded

3 tbsp (45 mL) Parmesan cheese, grated