Place the whole chicken on a clean work surface. Remove the innards and pat dry with paper towels. Season the chicken with salt and pepper (inside and outside).
There are two ways to make the soup. With a boil first stove top, or letting it completely cook in slow cooker.
Stove top prep:
I like to do it first in a soup pan stove top and skim off fat. If you would like to do that way, start with this step. Place chicken in large soup pot with cover (I used my 7 quart nonstick Dutch oven). Add enough water to cover the chicken.
Add in the onion, carrots and celery and the chicken. Bring to a boil and then lower heat to a low boil and begin to skim the fat (lots of foam should be floating to the top) off. Do this until most of the foam has been removed (should take 10 minutes or so).
Very carefully transfer the chicken in the water with the vegetables into your 6-quart or larger slow cooker.
Slow cooker (no stove top prep):
Place the vegetables in the slow cooker. Add the chicken on top of the vegetables and the water. Add in your bouillon paste or cube, if using. IF you don’t have any bouillon paste or cube, add less water and add a box of your favorite stock or broth.
Add in the bay leaves.
Cover with the lid and set the slow cooker to HIGH and cook for about 6 hours (could be ready in less since you bring to a boil on top of the stove). Or cook for about 8 hours on the LOW setting. until the chicken is cooked through and reaches an internal temperature of 165 degrees F. The cooking time can vary greatly depending on your slow cooker model, so check the thickest part of the chicken to see if it's done early to ensure it does not overcook.
During the 30 minutes of cooking, add in a bunch of fresh parsley and dill (not chopped).
Turn the Crock-Pot off, discard the bay leaf, parsley and dill bunch, and carefully remove chicken from the crock onto a cutting board (it will be falling apart). Let the chicken cool for 10-15 minutes, then shred chicken, discarding skin, bones, and cartilage.
Skim any accumulated fat off of the soup and return the shredded meat back to the soup (I usually use a mesh strainer to remove unwanted particles from the broth before serving, cheesecloth also works to strain.
Cut carrots and celery (if you’re serving with celery)and cut into small pieces.
Taste soup and add additional salt, pepper, fresh parsley if desired, then serve.