This is by far the BEST Loaded Mashed Potato Casserole! Creamy mashed potatoes combine with sour cream, butter, and cheese to make the base of the dish. Next, we add crispy fried onions, smoky bacon, and tangy Ranch dressing to take it over the top! It's the perfect potato casserole for holidays, lazy weekends, or any time you need an easy, yet delicious potato side dish.
Potatoes are one of my favorite things to eat in this world and I wish I could eat them every day, in one form or another! Although that is extremely unrealistic, I can dream, can't I?
That being said, this is my favorite mashed potato casserole in the world! I use this recipe all the time and have for years. It uses a secret ingredient to add flavor -- sour cream dips! From French onion dip to jalapeno cheddar dip the possibilities are an endless number of flavor combinations.
Even better this mashed potato casserole goes with a whole range of main dishes including my hamburger steak with onion gravy or your holiday turkey dinner.
If you love potato casseroles you've got to try this spicy potato casserole and cheesy potato casserole next!
Why You Will Love This Mashed Potato Casserole Recipe
- Versatile Recipe: The truth is you can put in as much or as little of anything and everything until the mashed potatoes taste the way you love. Remember to taste as you go.
- Family Favorite: This loaded potato casserole is a popular dish for holidays, weeknight dinners, and so much more. Everyone loves it!
- Perfect to Make Ahead: Make it in advance to get ahead on your holiday cooking or to make dinnertime easier.
Ingredients
Here's a look at what you need to make cheesy mashed potato casserole.
- Russet potatoes: My favorite potato for making creamy, fluffy mashed potatoes. You can also use another type of all-purpose potato such as Yukon gold potatoes. Don't waste your peels! You can make some crispy potato skin chips with them instead.
- Butter: Adds richness and flavor.
- Milk: Combines with the butter to create a flavorful potato dish but also thins the potatoes out making them creamy and delicious.
- Sour cream or sour cream-based dip: Added to make the potatoes even creamier and richer. You can stick with sour cream or use your favorite dip with sour cream to add flavor!
- Cheese: I prefer a combination of shredded cheddar and Monterey Jack cheeses but you can use any combination of cheese that melts well.
- Seasoning: Garlic salt and pepper are all that's needed to enhance the flavor.
- Loaded potato options: Choose from green onions, ranch seasoning, and bacon, and crispy fried onions!
See the recipe card below for the full ingredient list and exact quantities of each ingredient.
Variations
- Spicy: Stir in some diced jalapeno or canned green chilies to your mashed potatoes. Top with a Mexican cheese blend or some pepper jack cheese.
- Broccoli Cheese Potatoes: Stir in some cooked chopped broccoli into the potatoes before adding them to the casserole.
- Cream Cheese: Swap the sour cream for cream cheese for creamier and tangier mashed potatoes.
How to Make Mashed Potato Casserole
Ready to get started? Here's a look at the easy method for making this potato dish.
Step 1: Boil your peeled and chopped potatoes for 15-20 minutes or until soft.
Step 2: Mash the potatoes in a large bowl. Add the butter butter, milk, sour cream, ranch, cheese, garlic salt, and pepper.
Step 3: Transfer the mashed potatoes to a prepared casserole dish. Top with cheese and bacon or crispy onions.
Step 4: Bake at 400 for 25-30 minutes until the top is golden brown. Top with chives and any other extras preferred.
⭐️ Hint: Taste your potatoes after mixing and before you add them to the casserole dish to ensure they're perfectly seasoned.
If you love potato recipes you may also enjoy this Cheesy Scalloped Potatoes or this Meatballs and Mashed Potatoes recipe!
Storage
- Storing: Place leftovers in an airtight container and store for up to four days in the fridge or up to three months in the freezer. Thaw in the fridge overnight before serving.
- Reheat: Use the microwave to heat individual servings quickly and easily. You can also return the potatoes to a casserole dish, cover with foil, and bake in a 350° F oven for 12-15 minutes until heated through. Top with more toppings and cheese if desired.
- Make Ahead Mashed Potatoes: Prep the entire dish except for the toppings. Wrap it well and store it in the fridge for up to two days. Allow the casserole to sit at room temperature before baking. Add the toppings and bake for 50 minutes.
Serving Suggestions
- Enjoy these potatoes along with this Dr. Pepper ham, honey mustard glazed ham, or slow cooker turkey breast for any holiday dinner.
- They make a great weeknight side dish with my flavorful garlic chicken thighs, reversed sear chicken breast, or a juicy t-bone steak!
- Complete your meal with these balsamic green beans, glazed green beans and carrots, or broccoli crunch salad.
Need more ideas for what to serve with mashed potatoes? Check out this collection of mashed potato side dishes. I'm sure you will find something that is lip-smacking good and will make your family drool when they sit down at the dinner table!
Recipe Tips
- Want a Crispy Top. Broil the casserole for just a few minutes at the end of cooking to brown and crisp the cheese.
- Additional Ingredients. You can stir bacon, chives, or other ingredient mix-ins into the mashed potato mixture OR add them on top!
- Adjust the Quantities: Remember you can add more cheese, less cheese, or really change up any ingredient to make your casserole taste exactly how you love.
Recipe FAQs
Yes, you can! Follow the same instructions to mix up your mashed potatoes. Transfer them to a sprayed slow cooker and add your toppings. Cook for 2-3 hours on low heat or until heated through.
Sure! I prefer to peel them for a creamier consistency but the peels contain lots of nutrition so it's fine to keep them. Just be sure to scrub the potatoes very well.
Loaded Mashed Potato Casserole Video
Other Great Potato Recipes
Do you like potatoes? Here some recipes you may also like to try.
Ready to get cooking? Remember that you can print this recipe if you would like.
Cheesy Mashed Potato Casserole
Equipment
- casserole dish (8-10 inches long by 6-8 inches wide or equivalent)
- potato masher or hand mixer
Ingredients
- 8-10 russet potatoes
- 2 tablespoons butter
- ⅓ cup milk
- ½ cup sour cream or sour cream based flavored dip
- 2 ¾ cups cheddar and monterey jack cheeses shredded, divided
- 1 teaspoon garlic salt
- ½ teaspoon pepper
Optional Toppings or Mix-ins
- 2 tablespoons ranch seasoning or ¼ cup ranch dressing and only ¼ cup of milk
- chives or green onions
- ¼ cup parmesan cheese
- bacon or bacon bits
- diced green chiles or jalapeno
- crispy fried onions
Instructions
- Preheat your oven to 400 degrees.
- Peel and chop potatoes, then boil in salted water until soft, about 15-20 minutes. Drain and return to pot or a large bowl.
- Ideally, using a handheld mixer, add butter to your potatoes. I add butter first while the potatoes are hot so the butter melts easily.
- Add milk, sour cream, ranch (if using), cheese, garlic salt, pepper and any other option you want to include. Blend ingredients together. TASTE your potatoes and add more of whatever you think they need, if anything at all.
- Spray a casserole dish with cooking spray and press your potatoes into it. Try and make the top as even as possible.
- First, I sprinkle bacon all over the top (if using), then crispy fried onions, and parmesan cheese (if using). Last, I sprinkle between ½ - 1 cup of shredded cheddar and monterey jack cheeses all over the top. Sometimes a little more, sometimes a little less.
- Bake for 25-30 minutes until top is a golden brown. Sometimes I will broil for a minute or two to darken the cheese a little more, if needed.
- Top with chives or green onions. Serve as desired.
Video
Notes
- Want a Crispy Top. Broil the casserole for just a few minutes at the end of cooking to brown and crisp the cheese.
- Additional Ingredients. You can stir bacon, chives, or other ingredient mix-ins into the mashed potato mixture OR add them on top!
- Adjust the Quantities: Remember you can add more cheese, less cheese, or really change up any ingredient to make your casserole taste exactly how you love.
Nutrition
This post was originally published November 2019. It has been updated with new content and images.
Berta says
My family love this casserole and it is a part of our rotation. Thank you for sharing it. Your recipes are amazing.
Karin and Ken says
As always you're most welcome! We love this casserole too! I'm so happy to have you with me on my food journey. I will continue to do my best! Enjoy your day! Karin
Tanya says
Great casserole Didn’t include ranch because I didn’t have any but everything else was exactly the way we like it Crispy onions are great idea with the chip dip. Thank you i will be making this again You have good recipes
Karin and Ken says
I’m happy to hear that you are enjoying our recipes! The crispy onions and sour cream based dip make the casserole amazing in my opinion! Thank you for taking the time to comment! You made my day! All the best. Karin
Candace says
Best mashed potato casserole I skipped the ranch but the sour cream dip was amazing Such great flavour added and I can’t wait to try another dip next time THANK YOU
Karin and Ken says
You are most welcome. Perhaps next time you can try it with the ranch if you decide to try it! Glad to hear you enjoyed it! I love this casserole and am glad we are not the only people who do! All the best. Karin