Prepare all ingredients by chopping vegetables and mincing garlic.
Place the chicken breasts at the bottom of the crockpot.
Add sliced carrots, diced celery, and chopped onion over the chicken.
Sprinkle minced garlic, thyme, and bay leaf on top of the vegetables.
Pour in the chicken broth, ensuring the ingredients are covered.
Season with salt and pepper to taste.
Cover and set the crockpot to low for 6-8 hours or high for 3-4 hours.
Once cooked, remove the chicken breasts and shred them with two forks.
Add the shredded chicken back into the crockpot.
Stir in egg noodles and cook for an additional 30 minutes on high until noodles are tender.