Place the peeled and cut russet potatoes into a crockpot.
Pour broth over the potatoes and half of the butter, cubed.
Cover the crockpot and cook on high heat for 3-4 hours, or on low heat for 6-7 hours, until the potatoes are tender and easily mashed with a fork.
Once the potatoes are fully cooked, carefully drain any excess broth from the crockpot, and add the remaining butter, cream cheese, and heavy whipping cream. Cover and cook on high for 10 minutes.
Add salt. Using a potato masher or an electric mixer, mash the potatoes directly in the crockpot until smooth and creamy. Taste and adjust the salt as needed. Cover and keep potatoes on the warm setting until ready to serve.
Garnish the top of potatoes with fresh chives, parsley, or extra butter, if desired.