In a stock pot over medium heat, add butter. Once melted and hot, add onions, carrots, and celery. Cook until vegetables begin to turn brown and onions begin to turn translucent, about 3-4 minutes. Add garlic and cook an additional 30 seconds.
Add flour and poultry seasoning, stirring to coat vegetables and create a paste. Cook for 1 minute.
Add chicken broth, half & half, and egg noodles to pot, stirring and scraping bottom of pan to deglaze (if needed). Bring soup to a boil, cover, and reduce heat to low. Cook according to pasta package directions for al dente pasta (for my thin egg noodles, this was 3 minutes).
Add chicken and stir to combine. Remove from heat. If soup is still thin, allow to set for 5 minutes to allow soup to thicken. Do a taste test, season with salt and pepper if desired, then serve and enjoy.
If soup is too thin, allow to set for a few minutes to thicken. The pasta will continually soak up liquid and thicken the soup as it stands.
If soup is too thick, add more chicken broth or water until desired consistency is achieved.
Soup reheats well the next day, but may need a splash of broth or water when reheating.
Creamy soups and pastas generally do not freeze well, so I do not recommend freezing this recipe.