Asian Mushroom Soup

4 cups fat-free, reduced-sodium chicken broth

3 tablespoons reduced-sodium soy sauce

2 teaspoons grated fresh ginger

3 garlic cloves, crushed

3 cups assorted mushrooms, sliced (I like white buttons, oyster, shiitake, portobello and crimini; if using shiitake, discard stems)

3 cups white cabbage, cut in wedges

1 cup thinly sliced carrots

2 cups chicken breast, shredded

2 cups fresh udon noodles (or substitute cooked linguine)

1 cup thinly sliced green onions, with some of the green tops

2 cups shredded raw spinach or whole baby spinach leaves

Freshly ground black pepper to taste

1 tablespoon mirin (sweetened rice wine) (Optional)