To save cleanup time, cook the noodles first, and then use the same pot for the soup. Add the noodles to the soup just before serving so they don't absorb too much of the broth. You can bring the noodles to work in a zip-top plastic bag. Make the soup the night before, cool to room temperature, and refrigerate; reheat in the microwave or in a slow cooker set on HIGH.
Combine noodles, oil, and 1/2 teaspoon salt; toss well to coat.
Combine water and next 6 ingredients (through chicken breast) in a large Dutch oven; add 1/2 teaspoon salt. Bring to a boil. Cover, reduce heat, and simmer 30 minutes. Remove chicken from pan; cool slightly. Shred chicken with 2 forks.
Add carrot and mushrooms to pan; bring to a boil. Reduce heat, and simmer 6 minutes or until carrot is tender. Add shredded chicken, parsley, spinach, and remaining 1 teaspoon salt; cook 3 minutes or until spinach wilts. Stir in noodle mixture, lemon juice, and pepper. Cook 1 minute.
This recipe has been retested for Cooking Light Slow Cooker Tonight, 2012