Slow Cooker Mashed Potatoes — Make-Ahead, No Boiling Needed

On Thanksgiving the stove is the busiest real estate in the kitchen, and a big pot of boiling potatoes is usually right in the middle of it. Slow cooker mashed potatoes take the whole job off the stove: the potatoes cook slowly in milk, water and butter until completely tender, then mash right in the crock — no boiling, no draining, no colander, no steam cloud. Better still, the slow cooker then simply holds them warm for up to two hours, so they are ready when the turkey is, not when the potatoes happen to be. The result is the classic you expect — fluffy, buttery, properly seasoned mash — made the one way that actually suits a holiday schedule: early, quietly, and entirely out of the way.

Why This Recipe Works

• No boiling and no draining: the potatoes cook in just enough liquid to be absorbed and mashed in, so none of the potato flavour (or the butter) goes down the sink.
• Cooking in milk as well as water: the milk starts flavouring the potatoes as they cook instead of only being stirred in at the end.
• Warm dairy at mashing time: cream cheese and a splash of warm milk mash in smoothly; cold additions are what make mash gluey and lumpy.
• The hold-warm advantage is the real recipe: on the Warm setting the mash holds for up to 2 hours with an occasional stir, which no pot on a crowded stove can safely do.

Serve them under 5-Ingredient Slow Cooker Beef Stew

Tips, Substitutions & Storage

• Potato choice matters: Yukon Golds give a naturally buttery, creamy mash; Russets give a fluffier, lighter one. Avoid waxy red potatoes — they mash gluey.
• Do not over-mash: once the potatoes are smooth, stop. Overworking releases starch and turns mash gummy; a hand masher is safer here than an electric mixer.
• Even chunks, even cooking: cutting the potatoes to a similar size is what lets them all finish at the same time in the slow cooker.
• Make further ahead: mash fully, cool, refrigerate up to 2 days in the slow-cooker insert if it is fridge-safe (or a covered container). Reheat in the slow cooker on LOW for 1 1/2–2 hours with 1/4 cup (60 ml) extra milk, stirring once or twice.
• Garlic route: the smashed cloves cook with the potatoes and mash in invisibly — all of the flavour, none of the raw bite.
• Lighter version: skip the cream cheese, use low-fat milk, and halve the butter — add an extra splash of warm milk to keep the texture soft.
• Storage: refrigerate leftovers up to 4 days; reheat gently with a splash of milk, stirring, so the mash turns creamy again. Freezes up to 2 months; thaw overnight and reheat the same way.

Another set-and-forget slow cooker favourite: Slow Cooker White Chicken Chili

Frequently Asked Questions

Can you really mash potatoes in the slow cooker without boiling?

Yes. The chunks cook in milk, water and butter until completely tender, then mash right in the crock — no pot, no draining.

How long can mashed potatoes stay warm in a slow cooker?

Up to about 2 hours on Warm, covered, with an occasional stir and a splash of warm milk if they thicken.

Why did my mashed potatoes turn gluey?

Usually over-mashing or waxy potatoes. Use Yukon Gold or Russet, and stop mashing as soon as they are smooth.

Can I make slow cooker mashed potatoes a day ahead?

Yes: refrigerate the finished mash and reheat it in the slow cooker on LOW with extra milk for 1 1/2–2 hours.

Do I need to peel the potatoes?

For the classic smooth result, yes. For a rustic version, scrub Yukon Golds well and leave the peel on — expect a textured mash.

For another make-ahead holiday side, see Classic Green Bean Casserole — Make-Ahead Thanksgiving Side.

Slow Cooker Mashed Potatoes

Slow cooker mashed potatoes that cook in milk and butter with no boiling and no draining — fluffy, make-ahead, and held warm until serving.

Print Recipe Pin Recipe

Prep Time 15 minutes mins

Cook Time 4 hours hrs

Total Time 4 hours hrs 15 minutes mins

Servings: 12 servings

Course: Side Dish

Cuisine: American

Ingredients Method Notes

Ingredients

  

• 5 lb (2.3 kg) Yukon Gold potatoes (or Russets), peeled and cut into 1-inch / 2.5 cm chunks
• 3 cloves garlic smashed (optional)
• 1 cup (240 ml) whole milk, plus more warm milk as needed
• 1/2 cup (120 ml) water
• 1/2 cup (113 g) unsalted butter, cut into pieces, plus more to serve
• 1 1/2 tsp fine salt plus more to taste
• 1/2 tsp ground black pepper
• 4 oz (113 g) cream cheese, softened (optional, for extra richness and hold)
• 2 tbsp chopped chives or parsley to serve (optional)

Method

 

1. Lightly grease the inside of a 6-quart slow cooker. Add the potato chunks and garlic if using. Pour over the milk and water, dot the butter pieces on top and sprinkle over the salt.
2. Cover and cook on HIGH for 3–4 hours or LOW for 5–6 hours, until the potatoes are completely tender when pressed with a fork — a chunk should crush with no resistance.
3. Turn the slow cooker to Warm. Add the cream cheese if using and the pepper. Mash directly in the crock with a potato masher until smooth and fluffy, adding warm milk a splash at a time until the mash reaches your preferred consistency.
4. Taste and adjust salt and pepper. Smooth the top, add a small knob of butter, cover and hold on Warm for up to 2 hours, stirring once or twice and loosening with a splash of warm milk if the surface thickens.
5. Serve warm, spooned into a bowl with the melted butter pooled on top and chives or parsley scattered over.

Notes

Cook on LOW for 5–6 hours instead of on HIGH for 3–4 hours.