Spray slow cooker with cooking spray. Dump in the frozen cubed potatoes, chicken broth, water, diced onion, salt, and pepper. Stir together.
Cover with lid and cook on LOW for 6-8 hours.
When done cooking, mix together half & half milk and flour in a small bowl. Pour into the soup and add the cubed cream cheese. Cover with lid and let cook and additional 30 minutes.
If I'm not serving the soup right away, I will add the milk/flour mix and cream cheese, then cover with the lid and set the crock pot to the warm setting for 1-2 hours. It keeps well on the warm setting if needed.
Serve with bacon pieces, shredded cheese, and green onions.
The potatoes get so soft & tender that there really is no need to mash them up even more. If you do want no potato chunks, just be careful not to over mash the potatoes which results in too much of the starch being released which leads to gummy potatoes. As you stir in the milk and cream cheese, the potatoes will naturally fall apart. So the soup will be creamy but still have super soft chunks of potato.
I normally don't add ground pepper to lots of my recipes but you need it in this potato soup recipe. I always add it and it's never too much for the kids.
A 32 oz carton of chicken broth is 4 cups of chicken broth. You can also use 4 cups water + chicken bouillon instead of the carton of prepared broth.