Place chicken into a 6-qt slow cooker. Stir in chicken stock, garlic, onion, carrots, celery, thyme, rosemary and bay leaves; season with salt and pepper, to taste. Cover and cook on low heat for 6-8 hours; reserve 1 cup and set aside.
Remove chicken from the slow cooker and shred, using two forks.
In a large bowl, whisk together heavy cream, flour and reserved 1 cup chicken stock mixture.
Stir chicken, heavy cream mixture and egg noodles into the slow cooker. Cover and cook on low heat for an additional 30-60 minutes, or until pasta is tender and soup is slightly thickened. Stir in peas.
Serve immediately, garnished with parsley, if desired.