This post may contain affiliate links. Please see our disclosure policy.
Creamy, fluffy, and full of flavor, this Mashed Potato Casserole is the perfect way to prepare mashed potatoes for a gathering or the holidays. It's rich, buttery, and just indulgent enough to feel special.
If your mashed potatoes always seem to cool off before the turkey hits the table, this mashed potato casserole is your stress-free fix. It delivers the same comforting flavor you love, but in a make-ahead version that lets you actually enjoy your meal.
Kristen's Keys for Mashed Potato Casserole
For a mashed potato casserole that has everyone going back for seconds (and maybe even thirds), pay attention to a few key pointers.
- Prepare in advance. While you can bake this casserole right after assembling it, part of its charm is how well it works as a make-ahead holiday dish. Assemble and refrigerate it up to 2 days in advance, or freeze it for up to 1 month prior to baking. It's such an easy way to get a head start on your holiday meal.
- Use starchy potatoes. Yukon golds or russets are your best bet-they mash up smooth and absorb butter like a dream. Waxy potatoes (like red potatoes) can turn gummy.
- Use full-fat dairy. Sour cream, butter, and cream cheese give that classic rich texture. Lower fat versions just don't hold up the same way.
5-Star Reader Review
This was very easy to make and a big crowd pleaser! I especially liked being able to make it the evening before. Has been added to our favorites list! -Lana ⭐⭐⭐⭐⭐
How to Make Mashed Potato Casserole
While easy to make, this step-by-step section is provided to help you feel confident whether you are a seasoned cook or a beginner.
Step One: Cook Potatoes
Peel and cut your potatoes into even chunks, then place them in a large pot of cold, salted water. Bring to a gentle boil and cook until fork-tender, about 15-20 minutes.
👉🏻Start in cold water and heavily salt. This helps the potatoes cook evenly and be flavored from the inside out.
Step Two: Drain Potatoes
Once the potatoes are fork-tender, drain them in a large colander but don't stop there. Return the potatoes to the hot pan and simmer until all the moisture has evaporated-about 1-2 minutes.
👉🏻Don't skip this step! This This keeps your casserole fluffy, not watery.
Step Three: Mash Potatoes
Mash the potatoes using a potato masher or ricer until smooth and fluffy. Avoid using a handheld mixer for this step, which can make your potatoes gluey.
Step Four: Flavor the Potatoes
To make this casserole creamy and flavorful, mix in softened cream cheese, sour cream, melted butter, milk, minced onion (if using), salt, and pepper until creamy and combined. Add the eggs, and mix again (adding the eggs last allows the potatoes to cool slightly so the heat doesn't scramble the eggs).
👉🏻Why a Mixer Now? After mashing the potatoes, you can mix in the additions with a handheld mixer on low speed an not overwork the potatoes.
Step Five: Transfer and Chill (or Bake Right Away)
Spread the potato mixture into a greased 2-quart casserole dish. If making ahead, cover tightly and refrigerate for up to 48 hours. Otherwise, bake right away.
👉🏻Freezing the Casserole? Mix in an additional ½ cup milk, transfer to a freezer-safe baking dish, cover well, and freeze for up to 1 month.
Step Six: Bake and Serve
Bake at until the top is slightly browned and the center is warmed through. The edges will puff a bit, and your kitchen will smell like buttery heaven.
Recipe Modifications
- Make it Cheesy: Stir 1 cup shredded cheddar into the potato mixture and then top the casserole with an another cup of cheese before baking.
- Loaded Mashed Potato Casserole: Top with cheese and crumbled bacon before baking. Add chopped chives right before serving.
- Egg-Free Option: Simply omit the eggs. The casserole won't puff up as much, but it will still taste rich and creamy.
- Omit the Onions: If you don't care for onions, you can omit altogether or replace the grated raw onion with 2 teaspoons onion powder.
Make-Ahead Tips
This dish was built for planning ahead and designed to reduce stress at the holidays!
- Up to 2 Days in Advance: Assemble, cover, and refrigerate. Let it sit at room temperature for 30-60 minutes and bake for an extra 45-50 minutes.
- Up to 1 Month in Advance: Add an extra ½ cup milk, assemble in a freezer and oven safe baking dish (like a disposable foil baking dish), cover tightly with 2 layers of foil and freeze for up to 1 month. Thaw overnight in the fridge before baking.
- Traveling? Bake at home and keep warm in an insulated casserole carrier. It will keep warm for about an hour.
Serve this Mashed Potato Casserole alongside your holiday favorites like Baked Ham, Roasted Turkey, or even a juicy New York Strip Roast and watch it quietly steal the show. And if your family is anything like mine, don't expect leftovers. xo-Kristen
More Favorite Holiday Side Dishes
- Sweet Potato Casserole
- Classic Bread Stuffing
- Roasted Butternut Squash Salad
- Green Bean Casserole
- Corn Casserole
Mashed Potato Casserole
Video
Ingredients
- 3 pounds russet or Yukon gold potatoes, peeled, and cubed
- 8 ounces full-fat cream cheese, softened
- ¼ cup unsalted butter, melted
- ½ cup full-fat sour cream
- ½ cup milk, any fat percentage
- ½ cup finely chopped yellow onion, optional
- 1 teaspoon kosher salt
- pepper, to taste
- 2 large eggs, lightly beaten
Instructions
- Grease a 9x13-inch casserole dish or 3-quart baking dish generously with butter. Preheat oven to 350℉ (175℃) if baking immediately.
- Place potatoes into a large stock pan. Cover with cold water and add 2 teaspoons kosher salt. Bring the potatoes to a rapid boil, then reduce the heat to medium. Simmer until the potatoes are fork-tender (the chunks should fall apart easily when pieced with a fork.) Drain the potatoes and return to the hot pan. Place over low heat and simmer until all the moisture has evaporated-about 1-2 minutes.
- In a large bowl, mash the hot potatoes by hand with a potato masher. Once mashed.
- Add 8 ounces full-fat cream cheese, ¼ cup unsalted butter, ½ cup full-fat sour cream, ½ cup milk, ½ cup finely chopped yellow onion, 1 teaspoon kosher salt, and a pinch of pepper to the mashed potatoes and mix on low speed using a handheld mixer until combined and fluffy. Whisk 2 large eggs in a small bowl, then add to potato mixture and mix quickly to combine.
- Transfer the potato mixture to the prepared casserole dish, spreading it out into an even layer. If not baking immediately, cover tightly and refrigerate up to 48 hours.
- If baking immediately, bake at 350℉ (175℃) for 20-25 minutes, or until warmed through and slightly browned. If baking after refrigeration, let the casserole sit at room temperature for 30 minutes while the oven preheats, uncover, and bake at 350℉ (175℃) for 45-50 minutes.
Equipment
- 9x13 Casserole Dish (a beautiful dish for oven to table!)
- large stock pan (this one fits a ton)
- potato masher (or use a potato ricer for less lumps!)
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
This was very easy to make and a big crowd pleaser! I especially liked being able to make it the evening before. Has been added to our favorites list!
Wonderful, thank you for sharing.
I made this potato dish for company dinner Sunday and it was a huge hit! I left out the eggs but may try them in the recipe next time. I added onion powder and garlic powder and omitted the finely chopped onion, as I know some of my guests don't like onion. I would like to try the "cheesy" version next. These were scrumptious!!
If I want make ahead can I freeze the casserole? Do I bake it first or can I freeze it after assembling it?
Hi Kathy! I would recommend baking first, allowing to cool completely. Wrap well in foil and plastic wrap and freeze up to 1 month. Defrost in the refrigerator overnight. Unwrap the casserole, cover with a single layer of foil and then bake at 350 degrees F for 30-40 minutes, or until warmed through.
I’m sure the last thing you want is another question about the cream cheese lol but I want to make these for dinner tonight but there’s 2 feet of snow where I live and I don’t have any cream cheese so going to the store is not an option today! Can I omit the cream cheese?Mary
Hi Mary! I am always happy to help with questions 🙂 It certainly won't be the same without the cream cheese, but I am ALL about using what you have on hand. I would suggest increasing the sour cream to 1 cup and adding a bit more milk to thin if needed. Enjoy and stay warm and safe!
Kristen, thank you for this wonderful recipe! I need to make this ahead of time and freeze it. I saw in an earlier comment that you suggest freezing after baking, which I will do. I was wondering if you have ever done this and how it turned out? Any other tips for reheating? Covered with foil I assume and then remove to brown at the end of reheating? Thank you in advance! ~ Janna
Hi Janna. I would prepare in a freezer-safe baking dish, bake and allow to cool fully. Wrap in several layers of foil and freeze. Defrost overnight in the refrigerator and then bake for 30 minutes at 350 degrees F covered with 1 layer of foil, remove foil, and continue to bake for 10-15 minutes to fully warm through. I have done this with great results.
Does this recipe go into a 9x13 in. casserole dish?? Recipe says a 9 in.dish.
Hi Mary Beth! Yes, this recipe goes into a 9x13 pan or a 3-quart baking dish. I hope you enjoy and sorry for any confusion.
SO amazing!! Definitely decadent, but I made it for Thanksgiving and that’s what the holidays are all about. We will make this again!
The perfect holiday mashed recipe! And I LOVE the variations for that personal extra loving touch. Thanks a bunch for sharing...my XMas dinner will certainly be easier 😀
I hope you enjoy Josie--Merry Christmas!