01 -
Place peeled and diced potatoes in a 6-quart or larger slow cooker. Pour in chicken broth, then sprinkle with salt, pepper, and garlic powder. Slice ½ cup (1 stick) of butter and distribute evenly over the potatoes.
02 -
Cover and cook on low heat setting for 6 hours or on high for 3 hours, until the potatoes are tender when pierced with a fork.
03 -
Turn off the slow cooker and carefully drain off the remaining broth without disturbing the potatoes.
04 -
Add remaining butter, cream cheese, and sour cream (if using) to the potatoes. Cover and allow to sit for 10 minutes to soften and meld flavors.
05 -
Mash the potatoes using a potato masher or beat with a hand mixer. Gradually add milk or heavy cream, about 1 cup, until reaching desired smooth and creamy consistency. Adjust seasoning with additional salt and pepper if needed.
06 -
Transfer mashed potatoes to a serving dish and garnish with freshly chopped parsley or chives.