Slow Cooker Mashed Potatoes make an easy holiday side dish! These flavorful potatoes are cooked and mashed all in the same pot, with no draining required.
In the bowl of a 6-quart to 8-quart slow cooker, add the potatoes, garlic powder, onion powder, salt, and black pepper. Pour the water over the top, then cover with the lid.
Cook on high heat for 3 to 4 hours, until the potatoes are easily pierced with a fork. (Even at low heat, the potatoes are usually done within 4 hours.) Stir the potatoes once per hour, if possible, to prevent the pieces that are not submerged in water from browning against the sides of the pot. If you can't do this, it's okay, but you may see a few browned pieces in the final mashed potatoes. (The browned parts are still delicious!)
When the potatoes are fork tender, use a potato masher to mash them. Add in the butter, if using, and milk, and continue mashing until they are smooth. You may need to add in an extra cup of milk, and I also add in an extra ½ to 1 teaspoon of salt. (Start with just a ½ teaspoon at a time.)
Once the potatoes are seasoned to your liking, they are ready to serve right away. The slow cooker will keep them warm for up to 3 hours, but they will firm up as they sit, so be sure to add an extra splash of water or milk, and stir until they are fluffy again right before serving.
Leftovers can be stored in an airtight container in the fridge for up to 5 days. You can reheat mashed potatoes in a large skillet, with an extra splash of water or milk, and stir until they are heated through again.
Notes
Nutrition information is for 1 of 10 servings, planning for 8 ounces of potatoes per person. This information is automatically calculated, and is just an estimate, not a guarantee.* If you use Yukon Gold potatoes instead of Russet potatoes, you will not need to use as much milk for mashing. They aren't as dry as Russet potatoes, so start with only a 1/4 cup of milk, and add more as needed.• This recipe is vegan-friendly if you use vegan butter and your favorite non-dairy milk.