In a large soup pot place whole chicken, mushrooms, onion, celery, carrots, potatoes, diced tomatoes with their juices and then add enough cold water to cover by 1 inch. Bring to a boil over high heat. Then add parsley, garlic, 1 tablespoon of salt and pepper.
Reduce the heat to medium-low, cover partially with a lid. Let it simmer for 2 hours, or until chicken is falling off the bone. Remove chicken and let it cool, for 30 minutes or until cool to the touch. Reduce heat to low and let the soup continue to simmer.
Remove all the meat from the chicken and shred the chicken into large pieces. Discard the skin and bones.
In a medium sauce pan cook rice as directed on box. Once cooked set aside in a bowl.
Using a potato masher, mash the soup a few times, letting some of the potatoes get a little smashed. I don’t try too hard on this, I just mash 2-3 times and call it good. Add the shredded chicken and rice* to the pot.
You can serve the soup with the rice on the side, letting each person add the amount of rice they want. If you are freezing this meal, freeze it without the rice, then add the rice when you are going to serve it.*
Serve while warm and enjoy!