5 from 1 votes

Mashed Potato Casserole

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Cheesy mashed potato casserole with an easy bread crumb topping is a great family casserole that is also perfect as a holiday side dish. Made with Russet potatoes, light and fluffy potato that is super commonly used in home kitchens provides an excellent base for a seriously loaded potato casserole. This perfect side dish goes well with turkey, chicken, and pork.

Cheesy mashed potato casserole is a great substitute for mashed potatoes (the plain stovetop kind) and is one of the more accepted potato recipes for kids.

mashed potato casserole with cheddar cheese

Why mashed potato casserole just works!

Everyone loves potatoes: Who doesn’t love melty potatoes! There is a reason the comforting, filling, and savory warm potato is one of the best side dish choices ever. Homemade potatoes with fresh bagged potatoes may take a little bit longer in prep, but really have no comparison over the flaky boxed ones most people keep in the pantry. 

Make-ahead recipe: With loaded mashed potato casserole being able to be made and prepped ahead, it is also a perfect holiday side dish choice. It’s basically prepping potatoes, seasoning, combining melted butter, and baking with lots of cheese and panko bread topping. Prep, season, and bake making this make-ahead recipe a perfect holiday choice.

Leftover potatoes work too: While this recipe starts with fresh potatoes, it’s fine to use leftover mashed potatoes and start with adding the ingredients!

Ingredients 

This delicious cheesy potato casserole version is one of the best-mashed potato recipes. Even mashed potato purists will agree that adding garlic, Dijon, and cheddar cheese will turn regular potatoes into outstanding garlic mashed potato casserole in no time at all. These perfect potatoes will make a potato lover out of you!

Here are the ingredients this recipe needs, then scroll through to read the recipe, with final measurements at the bottom in an easy-to-use printable recipe post.

  • 3 lbs. russet potatoes – cut into 1″ chunks (no potato peels)
  • milk
  • sour cream
  • butter
  • Dijon mustard
  • minced garlic
  • salt and pepper
  • cheddar cheese
  • Italian bread crumbs
  • butter, melted

What to serve with potatoes: Air Fryer Chicken Tenders, Parmesan Chicken, Ritz Cracker Chicken, Alice Springs Chicken

How to make Mashed Potato Casserole

  1. Peel potato skins and cut into 1 inch chunks (this helps potatoes boil faster).
  2. Add potatoes to a large stockpot and cover with water, at least 1″ above the potatoes. Heat on medium high and boil potatoes until tender, easily sticking a fork into them. This typically takes about 15 minutes.
  3. Carefully drain excess water and return soft, warm potatoes to pan.
  4. Directly on the potatoes, add milk, sour cream, 4 tablespoons butter, Dijon mustard and minced garlic.
  5. Mix all ingredients together well and season with salt and pepper.
  6. Grease a 1-1/2 quart casserole dish with nonstick cooking spray.
  7. Spoon potato mixture into casserole dish and spread evenly.
  8. To the top of the casserole, add shredded cheese evenly over the potatoes.
  9. In a small bowl, combine bread crumbs and 2 tablespoons melted butter. Mix well.
  10. Sprinkle bread crumbs on top of cheese in dish.
  11. Bake potato casserole for 20-25 minutes or until center is hot.
  12. Remove casserole from oven and serve while cheese is melty.
mashed potato casserole recipe adding ingredients into a bowl
bread crumb and cheese topping into potato casserole

FAQ’s

What kind of topping goes best with mashed potato casserole?


Personally, I love cheesy mashed potatoes as is but there is something about a crispy topping that just takes this regular mashed potato recipe to a hold new (and totally unique) level.
Keeping it simple, panko crumbs are my very favorite choice, but I have been known to substitute Ritz Crackers, Italian Bread Crumbs, and even Lay’s potato chips (like my mom did on tuna casseroles) as I was growing up.

What other flavor variations go well with potato bakes?


Of course, this is only one way to make Mashed Potato and Cheddar Cheese casserole.
As you get to know the base recipe, it may be time to experiment with flavors and your side dish choices by adding garlic, bits of onion, chives, bacon pieces and even changing up the type of potatoes themselves. 
I have shared this recipe with so many people and had family and friends taste it and everyone has an opinion on ways to make it even more perfect for the holidays. 

Can mashed potato casserole be made ahead of time?


Absolutely! You can prep and assemble this casserole all the way up to the panko crumbs, then wait till adding those toppings till baking. This makes sure that the breading doesn’t soften in the fridge. As far as timing, the fridge makes casseroles extra cold, therefore either bringing the chill off by sitting at room temp for about 15 minutes prior to baking is helpful, or adding additional time as needed. 

How long can a mashed potato casserole stay good? 


 If you have leftovers, store them in the fridge for up to 3 days. Please note that panko crumb topping may soften in the fridge. 

There is no doubt that potatoes make the best and most traditional holiday side dish. There are so many ways to make potatoes that I had to share a few more recipes!

Try out super-viral Fouchy potatoes, a family recipe that belongs to the world now!

While the name Funeral Potatoes isn’t that flattering, this side dish with potato chip topping is SO good.

Russets are the most popular potato, but using baby potatoes provides different flavors and textures. Try out smashed red potatoes, creamer potatoes, or crispy parmesan potatoes for a new potato side each night.

5 from 1 votes

Cheesy Mashed Potato Casserole


Prep Time 10 minutes
Cook Time 35 minutes
Total Time 45 minutes
Cheesy Mashed Potato Casserole (also known as a mashed potato bake) is an incredible and well known side dish that takes stove top mashed potatoes to oven basked potatoes. Creamy, cheesy and completely easy to load up with tons of toppings, this mashed potato casserole even includes a crunchy panko crumb topping that will BLOW YOUR MIND. While potato side dishes really are perfect for dinner and a crazy good holiday side dish, do not discount leftover mashed potato casserole just for lunch as well.  Cheesy mashed potato casserole is a fantastic substitute for regular mashed potatoes. With lots of shredded cheddar cheese and a light but crispy bread crumb topping, this is a homemade holiday side dish that will complement the season deliciously.

Ingredients
 

Mashed Potato Casserole

  • 3 lbs. russet potatoes peeled and cut into 1″ chunks
  • 1-1/2 cups milk
  • 1/2 cup sour cream
  • 4 tablespoons butter
  • 2 teaspoons Dijon mustard
  • 1 tablespoon minced garlic
  • salt and pepper
  • 1 cup shredded cheddar cheese

Crumb Topping:

  • 1/2 cup Italian bread crumbs
  • 2 tablespoons butter melted

Instructions

  • Peel potato skins and cut into 1 inch chunks (this helps potatoes boil faster).
  • Add potatoes to a large stockpot and cover with water, at least 1" above the potatoes.
  • Heat on medium high and boil potatoes until tender, easily sticking a fork into them. This typically takes about 15 minutes.
  • Carefully drain excess water and return soft, warm potatoes to pan.
  • Directly on the potatoes, add milk, sour cream, 4 tablespoons butter, Dijon mustard and minced garlic.
  • Mix all ingredients together well and season with salt and pepper.
  • Preheat oven to 375.
  • Grease a 1-1/2 quart casserole dish with nonstick cooking spray.
  • Spoon potato mixture into casserole dish and spread evenly.
  • To the top of the casserole, add shredded cheese evenly over the potatoes.
  • In a small bowl, combine bread crumbs and 2 tablespoons melted butter. Mix well.
  • Sprinkle bread crumbs on top of cheese in dish.
  • Bake potato casserole for 20-25 minutes or until the center is hot. Keep in mind that all ovens heat at a different temperature so its important to watch your breadcrumbs.
  • Remove casserole from oven and serve while cheese is melty.

Notes

When boiling fresh potatoes
  • While Russet potato’s are recommended for this potato casserole, any type of potato (red, yellow, blue etc.) can easily be substituted for casserole variations.
  • Typically it takes about 15 minutes for cut potatoes to properly boil but just test with fork. Once tender, remove and drain.
What kind of topping goes best with mashed potato casserole?
Personally I love cheesy mashed potatoes as is but there is something about a crispy topping that just takes this regular mashed potato recipe to a hold new (and totally unique) level.
Keeping it simple, panko crumbs are my very favorite choice, but I have been known to substitute Ritz Crackers, Italian Bread Crumbs, and even Lay’s potato chips (like my mom did on tuna casseroles) as I was growing up.
What other flavor variations go well with potato bakes?
Of course this is only one way to make Mashed Potato and Cheddar Cheese casserole. As you get to know the base recipe, it may be time to experiment with flavors and your side dish choices by adding garlic, bits of onion, chives, bacon pieces and even changing up the type of potatoes themselves. 
I have shared this recipe with so many people and had family and friends taste it and everyone has an opinion on ways to make it even more perfect for the holidays. 
Using left over mashed potatoes
Making mashed potato casserole is even easier when you have left over potatoes. Simply warm up any left overs in a sauce pan and start with added ingredients. 
Can mashed potato casserole be made ahead of time?
Absolutely! You can prep and assemble this casserole all the way up to the panko crumbs, then wait till add those toppings till baking. This makes sure that the breading doesn’t soften in the fridge. As far as timing, the fridge makes casseroles extra cold, therefore either bringing the chill off by setting at room temp for about 15 minutes prior to baking is helpful, or add additional time as needed. 
How long can a mashed potato casserole stay good? 
 If you have left overs, store in the fridge for up to 3 days. Please note that panko crumb topping may soften in the fridge. 

Nutrition

Serving: 1 | Calories: 519kcal | Carbohydrates: 62g | Protein: 15g | Fat: 24g | Saturated Fat: 14g | Polyunsaturated Fat: 8g | Trans Fat: 1g | Cholesterol: 67mg | Sodium: 523mg | Fiber: 6g | Sugar: 4g

Nutritional Disclaimer: The nutritional data provided here is auto-calculated and intended for your convenience only. As it’s generated via automation, its accuracy may be compromised. For precise nutritional insight, please compute the values utilizing the actual ingredients in your recipe through your chosen nutrition calculator or application.

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5 from 1 votes

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3 Comments

  1. First time making this recipe,easy and so delicious. Am anxious to try other recipes. Thank you !!

  2. What temperature should the oven be?

    1. Trisha Haas says:

      Its listed in the recipe card and its 375. I hope this helps!

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