Wash and peel the potatoes. Cut into small chunks (1-2 inches; the smaller the pieces the faster they will cook).
Spray the slow cooker with nonstick cooking spray. Place the potatoes into the slow cooker. Sprinkle with in 1 teaspoon salt and ½ teaspoon black pepper; stir to coat. Slice stick of butter Into 8 tablespoons and arrange on top of the potatoes. Pour In broth, careful not to disturb the potatoes.
Cook on high for 3-4 hours, until the potatoes are very tender. Switch the slow cooker to the warm setting.
Mash the potatoes with a potato masher, or for a very smooth consistency, use a hand mixer.
Slowly stir in the warmed heavy cream, salt and pepper. Potatoes will be thick and creamy. Add more butter or cream until desired consistency and flavor is reached. Taste, and add salt and pepper as desired.
Keep mashed potatoes in the slow cooker on the warm setting until ready to serve; up to 4 hours.
Storage: Mashed potatoes should be stored in an airtight container in the refrigerator for up to 4-5 days or in the freezer for up to 3 months.Reheating: To reheat, microwave fully thawed potatoes on high for a one minute, then stir and continue heating in 30 second increments, adding a little cream or butter to make them creamy again.