Cheesy Mashed Potatoes Casserole

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A savory make ahead cheesy mashed potato casserole that’s easy to double or triple, making your holiday cooking to-do’s a whole lot easier!

All images and text ©Jenny DeRemer for Not Entirely Average, LLC

Cheesy Mashed Potatoes Casserole

America’s comfort food favorite gets a cheesy baked boost with the addition of melty cheddar and fresh scallions!

Mashed potatoes. Who says I can’t brag on this comfort food fave? I could oodle over mashers just about any night of the week. Admittedly, I am usually a boring starch seeker adding only the required butter and milk enough to get them ready and on the table.

But the weather is changing and I can taste fall in the air. Embracing comfort foods is just what we do during autumn. And recipes for comfort foods can never come soon enough for figuring out what to serve on our holiday tables.

Once assembled, this casserole bakes for 20 minutes total time. If you assemble it as a make ahead and refrigerate, it bakes for 30 to 35 minutes straight out of your chiller. I am now at the point of having invested in “pairs” of matching casseroles, and assemble TWO of these for the holiday dinner table.

Do You Have What’s Needed For This Cheesy Mashed Potatoes Casserole? Check The List!

russet potatoes
fresh chives
green onions
unsalted butter
sour cream, regular or low fat
cheese of choice; consider sharp cheddar cheese, gouda, or German Butterkäse

optional
southern dry-cured ham or prosciutto

How This Recipe Came About…

As I mentioned above, this recipe unfolded out of necessity. First, let me say this; I love leftovers at the holidays. I CRAVE that day after turkey sandwich outfitted with a layer of cold stuffing, a slice of cranberry sauce, mayonnaise, and pepper all between a couple of quality slices of white bread.

But sometimes, there aren’t much in the way of awesome re-heatable leftovers like mashed potatoes. Face it people, the mashed are the first to get wiped out once the casserole dish is passed. The night after that Thanksgiving gobbler, I want to re-live the glory of the feast with a hot plate of everything that made the day before so special!

This recipe serves two purposes. When I know I am automatically going to want leftovers, this mashed potatoes recipe loaded with lots of shredded cheddar cheese is easy enough to make an extra of. I just pop it into my fridge for the next day.

It goes with really good chicken recipes like herb baked chicken, delicious Chicken Française, any steak and potatoes recipe really, and all this in addition to Tom Turkey. But this recipe is also fabulous if you just want to get ahead of meal prep any time.

This casserole, once assembled, keeps in the refrigerator for up to 3 days before it must be baked. And if I do decide to double the recipe? Should it happen that additional faces show up on the day of the feast, I have not one, but two casseroles and enough to please everyone!

What’s The Best Potato To Use For Mashed Potatoes?

Russets and Yukon Golds. These are my picks and also my solid recommendations. Why? Buttery flavor and a pleasing texture make for the absolute fluffiest, smoothest, and most flavor-packed mash. Choose one or the other or mix them.

Salt early. That is to say, use Kosher salt and salt the water you will use to boil the potatoes in. Salting early means the swollen starch granules will absorb that salt, making it so you won’t have to salt heavily at the end.

AND always, always, always cover them with cold water, then add the salt, then boil and reduce to a simmer. This ensures they will cook evenly.

What’s The Best Cheese For Mashed Potatoes?

So here I go with cheese again! I usually have a big block of sharp cheddar cheese in my chiller. I shred from a block ALWAYS, and very seldom purchase pre-shredded cheese. Why?

Partly because of the additives in shredded cheese that are present to ensure the cheese won’t clump. You know, stick together. But my point is additives…

So, there’s that…and shredded cheese also has a ton of surface area. Of course because it’s SHREDDED. And, because we’re talking cheese, all that additional surface area gives mold so much more room to colonize.

A block cheese, wrapped tightly in plastic film after being opened, can keep in the fridge for weeks. Shredded cheese must pretty immediately be used or be frozen.

So yeah, I grab whole blocks of cheese for those reasons alone. For this recipe, I like cheddar and even Gouda. But I always make a point of purchasing a block of German Butterkäse for this if I remember to. What is Butterkäse? Translated, it’s “butter cheese.” But not really!

Butterkäse is a truly versatile cheese that’s a refreshing alternative from typical cheddar. It’s a mild semi-soft cows milk cheese traditionally made near the Swiss border in Germany as well as in Austria. It is now also produced in Wisconsin! It is utterly melty and so mild it passes the ‘kid test.’

What Other Ingredients Can I Add To This Cheesy Mashed Potato Recipe?

Gosh, so much comes to mind, but I’ll try to name the top handful that I have tried with success. And remember, the choice of cheese is yours. So is the option for a salty dry-cured ham or the closest thing to it which is prosciutto.

• seared, chopped pork belly
• caramelized onions
• crumbled bacon
• French fried onions in the can
• freeze-dried potato sticks in the can (we called them hay stacks)
• a head of roasted garlic cloves for garlic mashed
• cooked and taco-seasoned ground beef

How To Make Cheesy Mashed Potatoes?

So believe it or not, there are ways to absolutely ruin mashed potatoes. Have you ever had them whipped ’til they look and taste like paste? Yeah, there’s a right way and a wrong way to whip a potato, as overworking them makes only for a starchy, pasty bowl of mashers.

• make sure to drain the potatoes well after cooking to avoid a watery mess – try returning them to the pan and steaming the remaining moisture out over an ‘off but still hot’ burner
• butter should have time to come to room temperature before melting it into the hot potatoes
• warm the milk or cream or stock you intend to mash with to avoid a cold liquid cooling the hot potatoes down – this is also a good time to ‘steep’ the liquid with fresh herbs or fresh garlic if using
• don’t get carried away and overwork your spuds – mashing too vigorously or for too long releases lots of starch, which makes them gluey and altogether unappetizing

Modifying The Norm To Make It Not Entirely Average…

So in addition to the list above, there are a couple of additions for occasions that may call for special ingredients. I saved these ingredients for making baked cheese mashed potatoes not entirely average. And these are all legit delish comfort-food fave additions that I myself have tried and met with rave reviews for.

This casserole was FABULOUS with a combination of broiled lobster meat and Muenster cheese with a drizzle of nutty brown butter over the top. I have also done this with barbecued smoked pork and American cheese with thinly sliced jalapeños scattered over the top.

Only YOU know your eaters, so be sure to cook for what they’ll ask you for seconds of!

How Long Does It Take To Make Cheesy Mashed Potatoes Casserole?

Remember, this casserole is make-ahead. If you do use it for this reason, assemble right in the baking dish and cover with plastic film and refrigerate until ready to bake. Straight out of the chiller, plan on a 30 to 35 minute bake.

If however you’ve assembled and plan to bake the casserole right away, load the baking dish into a preheated oven and let it go for 20 to 25 minutes. The creamy edges and the bits of visible cheese will be bubbling!

I make a point of separating (mostly) the white parts from the green parts of my scallions. I saved the white parts for scattering on the top. They are something extraordinary baked atop the casserole this way. They too, will show signs of doneness when they just begin to brown up.

What To Serve Cheesy Mashed Potatoes?

Hey y’all, what’s NOT to serve with cheesy mashers??? Think steak and potatoes, chicken and potatoes, and a scoop of this casserole by itself with a tossed salad! Okay, who’s salivating?

What To Drink With Cheesy Mashed Potatoes?

As the recipe is written, this side dish compliments a medium white wine like chardonnay, Semillon, or a crisp German Riesling. Red wine lovers will enjoy it with a robust zinfandel, and I highly recommend anything “old vine” and with notes of clove and cinnamon especially if you are adding the salty ham/prosciutto.

As for beer, a light lager, especially a crisp Pilsner, is the best complement to cheesy mashed potatoes.

Can I Freeze Leftover Portions Of Cheesy Mashed Potatoes?

Yes, and it’s why this also makes a great make ahead side dish for those busy school nights.

For a whole casserole, assemble the recipe following the directions stopping just before baking it. Assemble in a freezer safe glass baking dish with a tight fitting lid or with a double layer of aluminum foil. After marking with the contents and the date of freeze on the outside, place flat into the freezer. Freeze for up to three months.

For freezing leftover portions which have already been baked, spoon into a freezer safe plastic container with a tight-fitting lid, then mark with the contents and date of freeze noted on the container. Freeze for up to three months.

To thaw, place in the refrigerator overnight. For a whole casserole, once completely thawed, bake as directed on the recipe card as it will be being baked for the first time. For completely thawed, previously baked portions, heat gently in the microwave until hot.

Cheesy Mashed Potatoes Casserole

Jenny DeRemer

A savory make ahead cheesy mashed potato casserole that's easy to double or triple, making your holiday cooking to-do's a whole lot easier!

3.75 from 4 votes

Servings: 8 servings

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Prep Time 20 minutes mins

Cook Time 35 minutes mins

Total Time 55 minutes mins

Course Side Dish

Cuisine American

Servings 8 servings

Calories 294 kcal

Equipment

• 8 x 8-inch or 9 x 9-inch casserole dish

Ingredients

 

• 4 pounds russet potatoes
• Kosher salt for salting the potato water
• 2 tablespoons chives fresh, chopped
• 1 bunch scallions chopped, white and green parts separated
• ½ cup + 1 tablespoon unsalted butter brought to room temperature, divided
• 1 cup sour cream brought to room temperature
• 1 cup cheese any kind, shredded

Instructions

 

• If planning to bake immediately, preheat oven to 350°F. Butter an 8 x8-inch or a 9 x9-inch casserole with 1 tablespoon of the butter. Set aside.
• Peel and quarter the potatoes and add them to a large stock pot. Add enough COLD tap water to cover by 1/2-inch. Sprinkle with Kosher salt, about 1/2 tablespoon.
• Bring the pot to a boil and boil the potatoes for about 15 minutes or until a fork will stab them without resistance.
• Melt the butter. Using a hand mixer or a potato masher, add to the potatoes and mash coarsely. They need not be smooth yet. Add the sour cream. Mash until smooth. DO NOT overwork the potatoes.
• Fold the chopped chives, dry-cured ham or prosciutto if using, and the green parts of the scallions into the mashed potatoes, along with the shredded cheese. Spoon the mixture into the prepared casserole dish. Scatter the remaining white parts of the scallions over the top.

You can bake the casserole now or cover and refrigerate for a later bake.

• To bake the casserole immediately, place into the preheated oven and bake for 20 minutes or until top is lightly golden and scallions are beginning to brown.

  If baking the casserole at a later time, pull it from the refrigerator and let it stand for 10 minutes while the oven preheats. Place into the oven and bake for 30 to 35 minutes or until lightly golden and scallions are beginning to brown.

Notes

Please Note that table salt and iodized salt are NOT substitutions for Kosher salt. Do not use table salt or iodized salt in any of the recipes you find on Not Entirely Average UNLESS specified otherwise.

To Freeze:

For a whole casserole, assemble the recipe following the directions stopping just before baking it. Assemble in a freezer safe glass baking dish with a tight fitting lid or with a double layer of aluminum foil. After marking with the contents and the date of freeze on the outside, place flat into the freezer. Freeze for up to three months.

 

For freezing leftover portions which have already been baked, spoon into a freezer safe plastic container with a tight-fitting lid, then mark with the contents and date of freeze noted on the container. Freeze for up to three months.

 

To thaw and heat: 

Place in the refrigerator over night.

To heat a whole casserole, once completely thawed, bake as directed on the recipe card as it will be being baked for the first time.

For previously baked portions, heat gently in the microwave until hot.

Nutrition

Serving: 1servingCalories: 294kcalCarbohydrates: 42gProtein: 9gFat: 11gSaturated Fat: 6gPolyunsaturated Fat: 1gMonounsaturated Fat: 3gTrans Fat: 1gCholesterol: 30mgSodium: 123mgPotassium: 1011mgFiber: 3gSugar: 2gVitamin A: 390IUVitamin C: 14mgCalcium: 166mgIron: 2mg

Keyword cheddar mashed potatoes, cheesy mashed potatoes casserole, cheesy mashed potatoes recipe, make ahead mashed potatoes

Tried this recipe?Let me know how it was!