A mashed potato casserole is thick and cheesy, with all the flavors of a twice baked potato but in casserole form. Make it ahead of time for a large gathering or potluck. It’s a great alternative to mashed potatoes.
Have you every tried to come up with something to take to a potluck or dinner that you can make ahead, is easy to warm up, and everyone will love? Twice baked mashed potatoes check off all the boxes. Everything you love about a loaded bake potato all in one dish.
This recipe has all the flavor and texture of a loaded baked potato – butter, cream, green onions – but it’s baked in a casserole dish! With a crowd pleasing recipe like this one, you can serve it for family dinners, holiday dinners, or take it to your next potluck! The options are endless.
Casseroles have always been a favorite of mine, they’re so easy to throw together and most of the time they can be prepared ahead and baked when needed. A broccoli and cheese casserole along with an easy sweet potato casserole are some of my go-to casserole recipes.
When it comes to potato casseroles, some meals call for rich and savory like scalloped potatoes or crispy au gratin potatoes, but for those times when you want a loaded baked potato flavor but in casserole form, try making a twice baked potato casserole.
Twice baking gives all of the flavors a chance to come together. A little garlic along with the green onions make them so much more interesting than traditional mashed potatoes. The eggs and long cooking time gives them a thicker texture, and the cream cheese makes certain that they’re creamy.
A tried and true potato side dish recipe is especially great to have in your back pocket for those occasions when someone wants you to bring a something that will feed a crowd. This casserole will easily feed 10. You can also half the recipe if you don’t need quite that much.
Twice baked mashed potatoes will go with almost any meat dish that’s on the menu. While everyone loves creamy mashed potatoes, they don’t travel well and they require some last minute cooking, not so with mashed potato casserole.
Why mashed potato casserole?
- It’s a simple recipe that easily feeds a crowd
- You can make it ahead of time and bake when you’re ready
- Add or omit toppings to make it just how you want
- The best recipe to bring to a potluck! Everyone loves it
- It has all the flavors of a fully loaded baked potato
Can I prepare this casserole ahead of time?
Yes! Make this casserole ahead of time and store in the fridge before baking. A great way to save some time if you’re busy or making other dishes on the same day. Simply add it to a casserole dish, cover with plastic wrap or a lid, and store in the fridge for 1-2 days.
Twice baked mashed potato ingredients
- Potatoes – Russet potatoes are the best type of potatoes for this casserole. They’ll mash smoothly and absorb all of the incorporated flavors. Yukon golds are second best but again, russet will have a thicker texture.
- Butter – you can’t have mashed potatoes without butter!
- Garlic and Green onions – these provide flavor.
- Milk – whole milk will result in creamier, more flavorful potatoes, you can also use half-and-half or even heavy cream.
- Cream cheese – Make sure your cream cheese is room temperature so it more easily combines with the potatoes.
- Cheddar cheese – Sharp cheddar cheese is my go-to but use whatever you like. In addition, freshly grated cheese will melt better than packaged shredded cheese.
- Eggs – this gives the casserole more texture than what you have in traditional mashed potatoes.
Steps to make a mashed potato casserole
Step 1: Prepare
Peel and cut potatoes into chunks. Boil until a fork will go into them easily.
Step 2: Add some flavor
Cook the garlic and green onion in a skillet until softened.
Step 2: Mash potatoes
Drain and mash the potatoes with a potato masher and add the green onions and garlic.
Pro Tip: As with mashed potatoes, it’s better not to use a mixer to make the potatoes creamy. If you don’t want any lumps use a potato ricer. Since these potatoes have onions and garlic, I like them a little lumpy so I use a potato masher.
Step 3: Get cheesy
While the potatoes are still hot, mix in cream cheese, some cheddar cheese, and the milk and eggs.
Add the eggs last so the potatoes will be a little cool and won’t curdle the eggs. Your mixture will be slightly lumpy.
Step 4: Bake
Add it to a casserole dish, top with some more cheese, and bake until the cheese is golden brown, about 45 minutes.
- Add more toppings – Add crispy bacon or parmesan cheese after the casserole is done baking.
- Leave out garlic and onions – If you’re not a fan of garlic cloves or green onions, feel free to omit them.
- Try marscapone instead of cream cheese, it’s not as tangy as cream cheese.
Mashed potato casserole FAQs
How to store cheesy mashed potatoes?
Store this casserole in an airtight container in the fridge for up to 3 days after baking. Reheat in the oven or in the microwave for easy and quick lunches. You can freeze a mashed potato casserole, the eggs keep it from breaking down.
Do you add warm or cold milk to mashed potatoes?
When adding milk to mashed potatoes, it’s best to to make sure it’s warm or room temperature. The potatoes will absorb room temperature liquid much better than cold.
What goes with twice baked mashed potatoes?
Although this recipe goes great with many main dishes, here are a few favorites.
- This pork tenderloin with apples is so juicy and compliments this casserole like no other
- For a classic and easy dinner, try it with these perfectly cooked smash burgers
- You can never go wrong with a brisket, especially with cheesy potatoes!
- Mashed potato casserole is a great addition to steak Marsala
More potato recipes you’ll love
If you loved this recipe, give it a star ⭐️⭐️⭐️⭐️⭐️ rating! Also, snap a picture of your finished dish and share it with me on Instagram using the hashtag #butterandbaggage and tagging me @butterandbaggage.
Twice Baked Mashed Potatoes
- 3 lbs Russet Potatoes 6 medium potatoes
- ½ cup Butter
- 1 bunch Green Onions
- 4 cloves Garlic minced
- 2 cups Milk
- 4 ounces Cream Cheese room temperature
- 8 ounces Cheddar Cheese 2 cups
- 2 eggs
- Preheat oven to 375º. Lightly grease a 9 x 13 baking dish.
- Peel and and cut potatoes into large chunks. Add to boiling water in a large pot and cook covered for 15 minutes or until tender with a fork. Drain potatoes.
- While the potatoes are boiling, add butter to a skilled and add green onions, cooking until softened, about 5 minutes. Add garlic and cook an additional minute.
- Add drained potatoes to a large bowl and mash with a potato masher. Add green onions and garlic. Add cream cheese and 1 cup of grated cheese, mix until melted then add the milk, eggs and salt. Stir until it is well combined and then spoon into the baking dish.
- Top with remaining 1 cup of cheese and bake for 45-50 minutes or until browned.
Barbara’s Tips + Notes
- Warming the milk up in the microwave before adding to the potatoes will help it absorb into the potatoes.
- Russet potatoes work best for this casserole but you can use Yukon Gold.
- If you want to add bacon, wait until after it has baked or the bacon will get too crispy.
- You can make this ahead of time and refrigerate before baking for a day.