Wash potatoes, and peel if desired. Cut into 1" chunks of even thickness.
Place potatoes and chicken broth in a slow cooker. Cover, and cook on high for 3 hours or low for 5-6 hours, or until potatoes are fork tender.
Add butter, sour cream, heavy cream, salt and pepper. Mash potatoes until no lumps remain. Add more cream as needed until desired consistency is reached.
Notes
You can leave the peels on or remove them, depending on preference.Mashing with a masher will keep the potatoes from becoming gluey. Alternatively, use a hand mixer to save time.