With a rich, gravy-like broth, this will quickly become your go-to chicken soup!
Heat the oil in a large pot over medium-high heat.
Saute the onion for about 2 minutes, until it becomes slightly soft. Add in the garlic; cook for 30 more seconds.
Add in the carrots, celery, and zucchini. Add in the salt, then cook for 6-8 minutes, until the vegetables have all become slightly soft.
Sprinkle the flour over the vegetables and stir to combine. Let the mixture cook for 1-2 minutes (don't let it start to burn).
Start pouring in your broth, about 1/2 cup at a time, stirring between each addition. The soup will thicken a little after each addition.
Once you've added in all your broth, bring the soup to a boil. Add in your sliced potatoes and stir to combine.
Tie your herbs together with some cooking twine, then tie the end of the twine to your pot handle. If you don't have cooking twine, toss the fresh herbs into the soup. If using dried herbs, stir them in with the rest of your ingredients.
Cook the soup on medium heat for about 10 minutes, until your potatoes are fork tender.
Stir in your cooked chicken, and season with salt and pepper to taste.