- Mix water and flour together and set aside.
- In a large pot, combine remaining water and milk and bring to a boil. Add the celery, onion, peas, carrots, thyme, green beans, corn, mushrooms, chicken bouillon, and return to a boil for 15 minutes, now add the potatoes and cook an additional 5 minutes or until the potatoes are soft.
- Add the chicken, and slowly whisk the flour and water mixture in while whisking.
- Cook until the soup thickens, and cool a bit.