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My go-to, make-ahead Crockpot Cheesy Mashed Potatoes with Caramelized Onions. Made simply and easily in the crockpot with cream, salted butter, onions, and melty Gruyere cheese. Each bite is perfectly smooth, creamy, and so delicious. This method makes for the creamiest and most flavorful mashed potatoes. You can make these in the crockpot, instant pot, or on the stove. They’re perfect for making ahead of time for easy entertaining!

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

I just could not do Thanksgiving without perfect mashed potatoes. After all, they’re everyone’s favorite side dish, right? My brothers are mashed potato fanatics. They say the only reason they love turkey and gravy is thanks to the forkful of mashers they add with each bite.

And while I definitely have other mashed potato recipes on the site, this is the family favorite. The crew really loves a cheesy, buttery potato with just the right amounts of onions. Not overpowering, but just right.

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

These are their perfect potatoes. I think I got the ratios just right! They’re now labeled as “fire” mashed potatoes.

Clearly, we love these potatoes.

After many years of trying all the ways to cook my mashed potatoes, I’ve decided that using the crockpot is my favorite. When in a time crunch, I use the instant pot or stove, but the crockpot is my ideal cooker.

I do mine a little differently than most.

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

Here are details

Most recipes for potatoes in the crockpot don’t have you cook the potatoes in water, then drain. They’ll tell you to cook in milk or broth. But I just don’t find that to work as well.

I add the potatoes to the crockpot, add water, add garlic, and salt, then cover and let them slow cook for a few hours or up to all day.

Once the potatoes are fork-tender, I drain them and add them back to the dry, but still hot crockpot bowl. I set the crockpot to low, then cook onions. The key is to allow the potatoes to sit in the hot crockpot to dry off. Reducing the moisture gives you even creamy, tastier potatoes!

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

While the potatoes sit, I make the onions.

A lot of mashed potato recipes call for onion powder. But I wanted to add a little more of a fresh onion flavor that wasn’t overpowering, but just right.

I love using caramelized onions for an onion flavor that’s more mellow.

I first caramelize them down in a bit of butter. Then I like to add some wine to help them caramelize a little faster. Next, just a little fresh thyme, sage, salt, and pepper. Plus lots of butter, which is key for any good potato dish.

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

When it comes to mashing the potatoes, I don’t do anything fancy, just mash them with a masher and call it a day. But you do you, if you love a super smooth, whipped potato, try using a potato ricer instead.

Once I have the potatoes mashed, I add cream, sour cheese, the carmelized onions, butter and melty gruyere cheese. Continue letting the potatoes cook until the cheese is melted. And that’s it, you’ll have the most perfect, flavorful, and creamiest mashed potatoes.

Classic, but with amazing flavor and cheesiness.

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

Serve these up warm with a little added sage for color.

I’m excited to not only share this recipe with you guys but also with family and friends. My brothers have all agreed, these are one of their favorite potato dishes.

When you win over the brothers, all is good!

The next question is, what will you be pairing these cheesy potatoes with? The obvious answer for Thanksgiving is turkey. But come December, over here it will be my roasted beef tenderloin.

Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

Looking for other easy Thanksgiving sides?? Here are my favorites: 

Crispy Parmesan Thyme Sweet Potato Stacks

Crispy Cheesy Potato Stacks

Sweet Potato Casserole with Sweet ‘n’ Savory Bacon Pecans

Easiest No-Boil Brie Mac and Cheese

Lastly, if you make these Crockpot Cheesy Mashed Potatoes with Caramelized Onions, be sure to leave a comment and/or give this recipe a rating! Above all, I love to hear from you guys and always do my best to respond to each and every comment. And of course, if you do make this recipe, don’t forget to tag me on Instagram! Looking through the photos of recipes you all have made is my favorite!

 

Crockpot Cheesy Mashed Potatoes with Caramelized Onions

Prep Time 30 minutes
Cook Time 4 hours
Total Time 4 hours 30 minutes
Servings: 8
Calories Per Serving: 521 kcal

Nutritional information is only an estimate. The accuracy of the nutritional information for any recipe on this site is not guaranteed.

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Ingredients

Instructions

Crockpot

  • 1. In the bowl of your crockpot, combine the potatoes, water, garlic, and salt. Cover and cook on high for 4 hours or on low for 6-8 hours, until the potatoes are fork tender. Set the crockpot to low or warm.
    2. Drain the potatoes, then add them back to the crockpot. Let sit, uncovered while you caramelize the onions.
    3. Melt together 4 tablespoons butter and the onions in a large skillet over medium heat. Cook, stirring occasionally until softened, about 10 minutes. Add the wine and continue to cook another 5 minutes until the onions are deeply caramelized.
    4. Add 4 tablespoons butter, the thyme, and sage, and season with salt and pepper. Cook another 2 minutes, then remove from the heat.
    5. Mash the potatoes with a masher. Add the cream and sour cream, adding more cream until your desired consistency is reached. Season the potatoes with salt and pepper. Stir the onions in with the butter and cheese, cover, and cook another 15 minutes, or until the cheese is melted and creamy. Keep the potatoes covered, on warm, for up to 4 hours.

Instant Pot

  • 1. In the bowl of your instant pot, combine the potatoes, water, garlic, and salt. Cover and cook on high pressure for 14 minutes. Release the steam, drain the potatoes, then add them back to the instant pot.
    2. Set the instant pot to warm. Let sit, uncovered while you caramelize the onions.
    3. Melt together 4 tablespoons butter and the onions in a large skillet over medium heat. Cook, stirring occasionally until softened, about 10 minutes. Add the wine and continue to cook another 5 minutes until the onions are deeply caramelized.
    4. Add 4 tablespoons butter, the thyme, and sage, and season with salt and pepper. Cook another 2 minutes, then remove from the heat.
    5. Mash the potatoes with a masher. Add the cream and sour cream, adding more cream until your desired consistency is reached. Season the potatoes with salt and pepper. Stir the onions in with the butter and cheese, cover, and cook another 15 minutes, or until the cheese is melted and creamy. Keep the potatoes covered, on warm, for up to 4 hours.

Stove

  • 1. In a large dutch oven, combine the potatoes, 6 cups water, the garlic, and salt. Bring to a boil over medium-high heat and cook 20-25 minutes, until the potatoes are fork tender. Drain the potatoes, then add them back to the pot.
    2. Finish as directed through step 3.
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Crockpot Cheesy Mashed Potatoes with Caramelized Onions | halfbakedharvest.com

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Comments

  1. 5 stars
    I made this last week for Friendsgiving and it was absolutely delicious and super EASY! I’m not a fan of gruyere cheese so I used fontina cheese instead. So good! A couple friends who typically don’t like onions loved this recipe. We’re having this again for Thanksgiving in a couple days.

    1. Hi Victoria,
      Awesome!! Love to hear that this recipe was enjoyed, thanks for making it and sharing your review:) Happy Thanksgiving! 🍽

  2. Hi! Do you think washing, peeling, and cutting the potatoes the night before would cause them to brown overnight? Thank you!

    1. Hey there,
      Nope, that should be okay for you to do! I hope you love this recipe, please let me know if you give it a try! xx

    1. Hey Krista,
      I like to use a potato ricer, it’s a game changer:) Please let me know if you have any other questions! xT

  3. Could I make the cheesy mashed potatoes ahead and reheat them in my crockpot?
    How long will this take to reheat on the medium heat level of crockpot using the 5lbs of potatoes recipe?
    Thanks so much!
    Kathy

    1. Hey Kathy,
      I would start reheating them in the morning and add cream to them as needed. Please let me know if you have any other questions! I hope you love the recipe! xx

  4. 5 stars
    I had intended to do a baked potato bar for my Bunco group the other night, but when I saw this recipe I did a 180 and switched it to a mashed potato bar. I had to modify a bit because I didn’t have Gruyere, so I used a combo of cheddar and Swiss. They were delicious all by themselves, but I also had various toppings; diced steak, diced chicken thighs, bacon, roasted asparagus bites, broccoli, sautéed mushrooms, and the usual cold toppings. Everyone raved about the spuds! I will definitely put these in my rotation of regularly made dishes!

  5. Hi! I would love to have the video back that you had put on your story making this… it’s so helpful! My question is about the garlic. You put it whole in the crockpot, but what do you do with it after? Do you toss it when you drain the potatoes, or do you mash it back together?

    1. Hi Ashlyn,
      Sorry, IG story videos only last 24 hours. You can toss the garlic after you drain the potatoes, unless you want a lot of extra garlic flavor then you can mash it with the potatoes. Please let me know if you have any other questions! xx

  6. 4 stars
    Doing a practice run of this before TG day in the Instapot. Is there any valid reason why I need to let the potatoes sit on warm while I caramelize the onions? I was thinking I could save some time, if I caramelize while it is cooking for 14 minutes. Thanks.

    1. Hi Christine,
      That would be just fine for you to do:) Please let me know if you have any other questions! Happy Thanksgiving! xx

    1. Hey Abby,
      You could totally do that, but you will want to add some additional cream or milk for reheating. Please let me know if you have any other questions! Happy Thanksgiving! xx

  7. Do you have a suggestion for a substitute for wine? I don’t drink and all that wine would go to waste.
    Looking forward to trying these!

    1. Hey Julie,
      Apple cider or broth would also work in place of the wine. Please let me know if you have any other questions, I hope you love this recipe! xT

    1. Hey Heather,
      Nope, you could also follow the stove top or instant pot instructions listed above:) Please let me know if you have any other questions! xT

  8. 5 stars
    Looks so delicious! We will make next week. My husband hates sour cream (even if it’s buried in a recipe)– is there a good substitute?

  9. Do you think these potatoes would lend well to being made the day before hand and warmed back up for Thanksgiving with a little extra liquid? Or could the onions be prepared ahead of time and added when the potatoes are cooked on Thanksgiving?

    1. Hey Julia,
      Totally, both of those would work well for you! I hope you love this recipe, please let me know if you give it a try! xx

  10. Hey there! This recipe sounds delicious, I want to make it for Thanksgiving! I’m obsessed with caramelized onions. But what would you recommend substituting the gruyere with? And I rarely use fresh sage and thyme and when I buy it for a recipe the rest goes to waste. So would it be ok to use dried/ground sage and thyme? If so, what amount do you think?

    Thank you for creating these delicious meals for us to try out! My husband and I love your recipes 🙂

    1. Is that cooking wine or regular white wine? Any suggestions for what wine to to you? I don’t know much I’m about wine , so any help would be great!

    2. Hey Josafina,
      Fontina or gouda would be great to use in place of the gruyere! A general rule of thumb is for every 1 tablespoon of fresh herbs you will want to use 1 teaspoon of dried herbs. I hope this helps! Please let me know if you have any other questions! xT

  11. Hi! Thank you so much for this yummy recipe! 🙂 Do you think the caramelized onions could be done the day before or would you not recommend this?

    1. Hey Allison,
      Sure, that would be okay for you to do! Please let me know if you have any other questions! Happy Thanksgiving! xT