Heat the oil in a large saucepan. Add the onion, carrot, celery, and green beans. Stir and cook for 4 to 5 minutes, until slightly tender. Stir in the garlic and cook 1 minute longer. Stir in the broth, seasoning, and pepper. Bring to a boil, reduce heat to low, and simmer for 15 minutes.
In a small bowl, whisk together the flour and milk until smooth. Stir it into the soup along with the peas and corn. Bring to a boil; cook and stir for 3 to 4 minutes, until thickened. Stir in the chicken and rice and heat through until the soup is creamy. If the soup thickens too much upon cooking or standing, it's okay to stir in a little extra chicken broth.
Notes
If you're counting WW Points be sure to use 2% evaporated milk.