Heat the olive oil in a pot over medium heat. Add the carrots, celery, onion, and garlic and sauté for 5 minutes, until the vegetables just begin to soften. Add the stock and bay leaf and cook over low heat for about 15 minutes, until the carrots are just tender. Add the chicken and noodles and continue cooking for about 5 minutes, just until the noodles are soft. Taste and adjust seasoning with salt and black pepper if necessary. Discard the bay leaf and garlic clove. Garnish with parsley before serving, if using.