Turn everyday mashed potatoes into something extra special with this creamy mashed potato casserole.
Loaded with bacon, cheese, and rich, buttery flavor, this comforting side dish is perfect for family dinners, potlucks, and holiday meals. It’s easy to make and always a crowd favorite.
Looking for more ideas? Be sure to browse all my Vegetable Side Dishes for even more easy and delicious recipes to serve with your meals.

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Table of Contents
- Recipe at a Glance
- Can You Make Mashed Potato Casserole Without Sour Cream?
- Main Ingredients Needed:
- Substitutions and Variations
- Step-by-Step Instructions
- Prepare the Onion and Bacon
- Insider Tips from My Kitchen to Yours
- Storage and Reheating Tips
- More Side Dish Ideas
- LOVE this recipe? SAVE it for Later!
- 🗒️Shopping List
- 📖 Recipe Card
- 💬 Comments
Recipe at a Glance
Prep: 15 min | Cook/Bake: 30 min | Difficulty: Easy | Servings: 6–8
Main Ingredients: potatoes, sour cream, cheddar cheese, bacon, butter
Best For: holiday dinners, potlucks, and family meals
Make Ahead: assemble ahead and refrigerate until ready to bake
Storage: refrigerate up to 3–4 days or freeze in airtight containers
You can serve this recipe alongside pot roast, classic beef stew, roast chicken or any of my favorite chicken cutlet recipes. It's even a great option for the vegetarian in your life...if you leave the bacon out!
Can You Make Mashed Potato Casserole Without Sour Cream?
If you don’t like sour cream, you can still make this mashed potato casserole and keep it creamy and flavorful.
Plain Greek yogurt is a great substitute and adds the same richness and moisture while the casserole bakes. You can use it in equal amounts for an easy swap.
Looking for more potato side dish recipes? Try my Air Fryer Potatoes, Prep-Ahead Company Mashed Potatoes or my Bacon Roasted Cheesy Potatoes...yum!

Main Ingredients Needed:
Here's a quick overview of the ingredients for this recipe. Find the exact amounts and click the Instacart button to easily add them to your cart – all in the printable recipe card below!

Substitutions and Variations
- You can also mix in veggies such as carrots or peas for a healthier, more flavorful side dish.
- Using different types of cheese, herbs, and spices - like chives, parsley, and paprika.
- Instead of bacon, you could add crumbled cooked sausage!
Step-by-Step Instructions
This section includes step-by-step photos and instructions to guide you through the recipe. For the complete printable version, scroll down to the recipe card below.

Step 1: Put the potatoes in a pot and cover them with water. Bring the water to a boil, then cook until the potatoes are easily pierced with a fork, approximately 20 minutes.

Step 2: Combine the potatoes with milk, sour cream, salt, and pepper, mashing them together. Set this mixture aside as you begin preparing the onions, garlic, and bacon blend.
Prepare the Onion and Bacon

Step 3: Heat the oil in a skillet. Then sauté the onion and garlic for a few minutes.

Step 4: Next, incorporate half of the cooked. And then add the crumbled bacon into the skillet with the onions and garlic.

Step 5: Mix the onion, garlic, and bacon blend into the mashed potatoes.

Step 6: Scoop the mixture into a 2-quart casserole dish that has been coated with non-stick baking spray. Sprinkle the top with cheddar cheese and the rest of the crumbled bacon.

Step 7: Place in a preheated oven set to 385°F and bake for 10 to 15 minutes until the cheese is melted and bubbling and the potatoes are heated through. If you want, sprinkle with sliced green onions just before serving.
Insider Tips from My Kitchen to Yours
✔️ DO use warm milk and butter when mixing the potatoes to keep the casserole smooth and creamy.
❌ DO NOT overmix the potatoes or they can become gluey instead of light and fluffy.

Storage and Reheating Tips
Refrigerator: Store leftover mashed potato casserole in an airtight container in the refrigerator within two hours of cooking. It will stay fresh for up to 3 to 4 days.
Freezer: You can also freeze the casserole in freezer-safe containers for later.
Reheating Tips: To reheat, place the casserole in an oven-safe dish, cover loosely with foil, and warm in a 350°F oven for about 15 minutes or until heated through. If frozen, thaw in the refrigerator overnight before reheating.


More Side Dish Ideas
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📖 Recipe Card

Mashed Potato Casserole with Sour Cream and Cheese
Ingredients
- 3 pounds potatoes peeled and cut into bite-sized pieces
- 8 ounces bacon cooked and crumbled
- 1 medium onion chopped
- 1 teaspoon garlic minced
- ¼ cup butter
- 1 cup sour cream
- ½ cup shredded cheddar cheese
- Salt and Pepper to taste
- 1 teaspoon vegetable oil
- ⅓ cup green onions sliced for garnish if desired
Method
- Preheat oven to 385°F,
- Add the potatoes in a large pot and cover them with water. Boil the potatoes until a fork goes through them easily.
- Drain the potatoes and transfer back to the pot.
- Add the ¼ cup butter and sour cream.
- Mash the potatoes. Season with salt and pepper.
- Set aside while you prepare the onions.
- Add the oil to a medium size skillet and allow it to heat.
- Add the chopped onions and garlic. Cook the onions for a few minutes until translucent.
- Then add ½ the bacon crumbles and allow them heat through and combine with the onions.
- Add the mixture to the mashed potatoes and mix all together.
- Transfer the potato mixture to 2 quart sized casserole baking dish that's been sprayed lightly with non-stick baking spray.
- Cover the potatoes with the shredded cheddar cheese.
- Sprinkle the remaining bacon crumbles over the top.
- Bake in the oven for 10 minutes or until the cheese is melted and the casserole is heated through.
- Garnish with the sliced green onions and enjoy.
Nutrition
Notes
Tried this recipe?
Let us know how it was!This recipe has been updated since it first appeared in 2015 with new photos, information and a new printable recipe card that includes nutritional information. I hope you enjoy the updates as much as I enjoyed working on them!








Catherine Sokolowski says
I need to make this for my daughter. I can't wait to surprise her the next time she comes for dinner.
Lois says
I hope you enjoy the recipe!
Moore or Less Cooking Food Blog says
Hi Lois!! Congratulations!! Your wonderful Mashed Potato Casserole is featured on our Simple Supper Tuesday Linky Party at Moore or Less Cooking Food Blog! Nettie
Miz Helen says
This is a great mashed Potato Casserole, it looks great. Thanks for sharing with Full Plate Thursday and come back soon!
Miz Helen
Michelle Nahom says
My kids would love this too! When my father in law was alive, he would cook Thanksgiving dinner and he would put bacon in everything and it became a tradition. This was our first Thanksgiving without him and my oldest son requested bacon in everything. LOL
Mitzi says
Oh my goodness--I think I just found my new favorite comfort food! Thanks for sharing at Motivation Monday 🙂
Nicole Neverman says
This casserole sounds amazing! What's not to love with that great ingredients list? If you had a spare moment, I would be delighted if you'd drop this (and anything else you'd like to share) by at the #PureBlogLove DIY and recipe link party! You can find me here: http://picnicnz.blogspot.co.nz/
Jessica Jarrell says
That looks yummy with a capitol Y! My husband would go nutty over this, definitely going to try it out on him! 🙂