In a large Dutch oven or stock pot over medium high heat, warm the oil. When the oil is hot and shimmering. add the onion, celery, and carrots. Cook, stirring often, until the onions are translucent and the other veggies are starting to get tender, 6-8 minutes.

Add the garlic and the chicken (raw or cooked) and cook until the garlic is fragrant, about 1 minute. Add the vegetable stock. Bring the mixture to a boil and then reduce the heat so that it simmers. Add the parsley. Simmer until the vegetables are tender, 10-15 minutes. Add the noodles and cook just until the noodles are al dente (the time will depend on the type you use), stirring often. Remove the soup from the heat and add additional herbs and salt and pepper to taste.