Peel and slice your carrots, chop the celery, and dice the onion. Add them to the bottom of your crockpot. Place the chicken breasts on top of the vegetables. You can season the chicken lightly with salt and pepper for added flavor.
Pour in the chicken broth until it covers the ingredients completely. Add the garlic, thyme, parsley, and bay leaf. Give it a gentle stir. Drizzle in a bit of olive oil for extra depth (optional but recommended).
Set your slow cooker to low for 6–8 hours or high for 3–4 hours. The long, slow simmer helps extract the flavors of the herbs, veggies, and chicken into the broth, creating a rich, savory base.
Once the chicken is fully cooked and tender, remove it from the crockpot and shred it using two forks. Discard the bay leaf, then return the shredded chicken to the soup and stir to combine.
If eating right away, add the egg noodles to the crockpot and cook for 15–20 minutes until tender. For best texture, cook noodles separately and add them just before serving. This prevents them from becoming mushy when stored.
Taste and adjust seasoning with additional salt, pepper, or a squeeze of lemon juice. Ladle into bowls and top with fresh parsley if desired. Serve warm with crusty bread or crackers.