Start by chopping your celery, onion, carrots, and mincing your garlic. Add them directly to your crockpot as you go along.
Place the chicken breasts on top of the vegetables in your slow cooker. Sprinkle with salt, black pepper, rosemary, thyme, red pepper flakes if desired, and add bay leaves.
Carefully pour in the low-sodium chicken broth until everything is submerged.
Cover your crockpot and set it on low heat for about four hours.
After four hours, remove the chicken breasts from the pot and shred them using two forks. Return shredded chicken back to the pot along with egg noodles. Stir everything together gently.
Cover again and cook on high for an additional 30 minutes until noodles are tender.