Heat the olive oil in a large pot (or Dutch oven) over medium heat. Add the onion, garlic, carrots, and celery. Sauté until the vegetables are tender, about 5 minutes.
Add the shredded chicken, Ranch dressing mix, and chicken broth. Cover the pot and bring the soup to a simmer.
Add the cream cheese and cheddar cheese and stir until the cheeses have melted and the soup is creamy.
Add the egg noodles and simmer until tender - about 5-7 minutes. Stir in bacon, but reserve some for garnishing the soup.
Serve the soup hot, garnished with the remaining bacon and chopped fresh parsley.