Preparation
Place the potatoes in the slow cooker and add the stock. Cover and cook on high for 2 hours, or until the potatoes are tender.
Using a potato masher, lightly mash the potatoes in the slow cooker, still leaving them fairly chunky. Gradually add the milk while mashing, until all of the milk has been incorporated. Mash until the potatoes are a consistency that suits you. Add the salt and pepper to taste and mix well.
Transfer to a serving dish and serve at once.