Things I did differently:
Cooked the chicken in a little olive oil in another pan since we didn't have leftover chicken.
Did not add the milk; not everyone here likes cream soup. The broth needed a little something more, so I added a little white wine instead (approximately 1/4 cup)
Added a little basil. We have fresh basil. Basil is good.
Used less potato--about 2 cups instead of 4. Just 'cause.
We don't have a Dutch oven, so I cooked the vegetables in a little olive oil in a deep pan, added the flour, and then one cup of broth & then put them with the rest of the broth and the cut up chicken in a soup pan.