Trim the fat from the chicken breasts and place in your slow cooker.
For the carrots, you can simply slice, or use a Japanese technique called Rangiri. To cut the carrots like this, cut a piece of the carrot off at an angle, then rotate the carrot 1/4 turn, cut another piece off at an angle, repeat the turning and cutting. This makes for bite size pieces that gives more surface area per piece.
Top the chicken with the onion, carrots, celery, thyme, rosemary, bay leaf, and salt and pepper as desired. Sprinkle the chicken stock powder over the top.
Pour in the broth and lightly stir.
Cover and set the slow cooker to Low setting for 6 to 8 hours or to Hugh setting for 3 to 4 hours.
Remove the chicken with a slotted spoon to a mixing bowl and shred with two forks. Find and remove the bay leaf from the slow cooker, then add the chicken back to the cooker.
Stir in the egg noodles, cover, and use the Low setting only, cook for another 10 to 15 minutes or until the noodles are tender.
Ladle into bowls, garnish with parsley and a shake of black pepper, enjoy.