Try this mashed potato casserole for when you are looking for a way to make instant mashed potatoes into something tastier. This recipe for Cheesy Mashed Potato Casserole combines mashed potatoes, sour cream, herbs, cheese, and more!
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Cheesy Mashed Potato Casserole
This recipe for cheesy mashed potato casserole is a unique potato side dish. It’s a casserole that combines mashed potatoes, sour cream, herbs, cheese, and crispy fried onions.
Try this mashed potato casserole with sour cream when you are looking for a way to make instant mashed potatoes into something tastier. This comfort food potato dish will be the star of your next meal.
This potato casserole recipe is comfort food in a big ole’ casserole dish: These creamy, cheesy mashed potatoes are exactly the most satisfying food to scoop up when it’s bleak and chilly outside. They’re a must-have for your winter table.
Why This is the Best Mashed Potato Casserole Recipe
This recipe is the best way to dress up mashed potatoes! This easy cheesy mashed potato casserole is so delicious that your family will ask for more every time.
It takes just a few simple ingredients and can be made in under 30 minutes.
This tasty side dish takes simple mashed potatoes up to a whole new level. The sour cream lends its signature tang to the potatoes, and then there’s the cheese….
This cheesy mashed potato casserole will make every other potato casserole look a bit boring by comparison. Stuffed full of delicious mashed potatoes, sour cream, and herbs and topped with shredded cheese and crispy fried onions, this casserole is even in-law approved!
Since this comfort food casserole bakes at the same temperature as many other dishes, you can be baking your entrée in the oven at the same time.
This recipe is a necessity when you have no time to shop for a long list of ingredients. All you need are the following:
- Instant mashed potatoes
- Sour cream
- Dried chives
- Dried parsley
- Black pepper
- Shredded cheddar cheese
- French’s Fried Onions
Cheesy Mashed Potato Casserole Recipe – Ingredient Substitutions
- Swap the sour cream for heavy cream or even cream cheese. If you want to reduce the fat content, use reduced-fat sour cream.
- This recipe uses Cheddar cheese, which melts wonderfully. You could combine it with parmesan, which adds its own signature salty, nutty flavor.
- Swap the Cheddar for fontina or gruyère, while pecorino is a great substitute for parmesan.
- For a vegetarian version, substitute a vegan version of sour cream and use a vegetarian-type cheese.
What About Using Fresh Potatoes?
I must confess that I have often fed instant mashed potatoes to my guests. If you add a few extra ingredients, most people won’t even know the difference.
Let me just say that you can, of course, make this cheesy mashed potato casserole recipe with fresh potatoes. I would use about two pounds of potatoes when making this dish from scratch.
How to Make Mashed Potato Casserole
- Prepare 4 cups of instant mashed potatoes according to the package directions.
- Add sour cream, chives, parsley, and pepper to the potatoes.
- Place the mashed potato mixture in a 1 1/2-quart casserole dish.
- Sprinkle cheddar cheese evenly on top.
- Place the crispy fried onions around the edge of the casserole.
- Bake at 350°F for about 20 minutes or until the cheese melts.
If you are making this dish ahead to reheat later, add the shredded cheese, but wait to top it with the fried onions until you are ready to reheat.
CopyKat Tip: Shred your own cheese. Cheese always melts better when shredded off the block. Pre-shredded bagged cheese contains anti-caking agents and preservatives that can hinder melting.
- Add some veggies – corn, peas, broccoli florets, diced bell peppers.
- Sprinkle on some fresh chives or thin slices of green onions when you take it out of the oven.
- Add more cheese and bacon crumbles to the topping. If you are not a fan of bacon, use cubed ham or sausage.
- Crisp things up by adding some crispy, toasty panko to your topping.
- Add a little sweetness to every bite with some cooked, cubed sweet potatoes.
- French onion soup your casserole! Add in one or two sliced, caramelized onions and a half cup of beef broth. Top with thin slices of Swiss or Gruyere.
A Brief History of the Potato
The Incas in Peru were the first civilization to cultivate potatoes around 8,000 to 5,000 B.C. After the Spanish Conquistadors conquered Peru in 1536, they discovered potatoes and brought them to Europe.
Potatoes landed in the US in 1621 when Nathaniel Butler, the Governor of Bermuda, sent vegetables, including potatoes, to the Jamestown colony in Virginia. Farmers everywhere eventually discovered that potatoes were easy to grow.
In time, it became known that potatoes contained nearly all of the vitamins necessary for human sustenance. You can read much more about the long history of the potato.
Some Interesting Facts About Potatoes
In the 18th Century Antoine-Augustin Parmentier, a French pharmacist convinced the French to eat potatoes and saved thousands from starvation during the European famines in the 1700s.
In 1767, Parmentier created a feast for King Louis XIV that consisted solely of potato dishes, a concept he realized was possible after being imprisoned in Germany and fed only on a diet of potatoes. Benjamin Franklin, the American Ambassador to France, attended Parmentier’s feast.
- During the Klondike gold rush in Alaska, (1897-1898), gold miners paid for potatoes in gold. Gold was plentiful but nutritious vegetables weren’t.
- In 1995, the potato starred as the first vegetable to be grown in space. NASA and the University of Wisconsin created a technology that would enable astronauts to be fed on long space voyages. It is hoped that in future potatoes will help feed human colonies on distant planets.
How to Serve Baked Mashed Potato Casserole
Many things go well with this potato side dish. This casserole is potato comfort food so deserves a robust entrée such as:
- Bacon Wrapped Pork Tenderloin
- Cracker Barrel Meatloaf
- Eye of Round Roast
- Oven Brisket
- Pan Seared Lamb Chops
What Other Vegetables Go Well With Mashed Potatoes?
How to Store Leftover Mashed Potato Casserole
Store leftovers in an airtight container in the fridge for 3 to 5 days. One awesome thing about this potato casserole is that you can make it ahead and refrigerate it.
This is super helpful if you’re making several dishes for a holiday meal or a large family dinner.
Note: Leftover mashed potatoes make great potato pancakes for breakfast. You might also check out bubble and squeak, a way in which the Brits love to use up mashed potatoes and anything else just taking up space in their kitchens.
Can You Freeze Mashed Potato Casserole?
Yes, you can freeze mashed potatoes. Simply scoop the potatoes into a freezer-safe bag and squeeze out as much air as you can. The potatoes will last in your freezer for 4 to 6 months.
If you are making this potato casserole ahead to reheat later or freeze, add the cheese topping, but hold off on the fried onions until you reheat.
To reheat, let the potatoes thaw in the fridge overnight. Then place them in a casserole dish and bake at 350°F for about 25 minutes. Add more cheese on top and bake for an additional 5 minutes.
Love Mashed Potatoes? Try these recipes!
- Champ – Irish Mashed Potatoes
- Cracker Barrel Mashed Potatoes
- Garlic Mashed Potatoes
- Leftover Mashed Potato Pancakes
- Mashed Purple Potatoes
- Old Fashioned Mashed Potatoes
- Yukon Gold Mashed Potatoes
Favorite Casserole Side Dish Recipes
- Asparagus Casserole
- Broccoli Rice Casserole
- Creamed Corn Casserole
- Green Bean Casserole with Cheese
- Squash Casserole with Ritz Crackers
- Sweet Potato Casserole with Pecan Topping
Mashed Potato Casserole
- 4 cups instant mashed potatoes
- 3/4 cup sour cream
- 1 teaspoon dried chives
- 1 teaspoon dried parsley
- 1/2 teaspoon black pepper
- 3/4 cup shredded cheddar cheese
- 1 cup French's Crispy Fried Onions
- Preheat the oven to 350°F.
- Prepare the instant mashed potatoes according to the package directions.
- Add sour cream, chives, parsley, and pepper.
- Place the mashed potatoes in a 1 1/2-quart casserole dish.
- Top with cheddar cheese.
- Sprinkle French's Fried Onions around the edge of the casserole.If you are making this dish ahead to reheat later, add the shredded cheese, but wait to top with French’s Fried Onions until you are ready to reheat.
- Bake for about 20 minutes or until the cheese melts.