Baked Loaded Mashed Potato Casserole

Loaded Mashed Potato Casserole is the most delicious way to repurpose up to 4 cups of leftover mashed potatoes. It’s loaded with bacon, cheese, sour cream and two kinds of onion, and topped with cheese crackers for good measure.

“This recipe is a winner! Easy to improvise if needed. I made it yesterday and it turned out to be melt in your mouth, delicious and memorable. Absolutely perfect way to use up leftovers!”

—Melinda

“Made this on Sunday before Christmas for our family Christmas meal. This was a huge hit! This recipe is now added to my favorites recipes.”

—Debra

“This is KILLER GOOD!! Took to a football party as a side. I felt bad… my dish went before the main one and other sides!!!”

—Patty

Ever Wonder Wha To Make With Leftover Mashed Potatoes? Here Is The Answer!

Thanksgiving is one of my favorite holidays, but with a gathering of just five people, we’re often stuck with quite a bit of leftovers after the big meal.

While you can simply reheat leftover mashed potatoes and drizzle them with gravy from scratch a second time around, my favorite way to serve leftover mashed potatoes is this Loaded Mashed Potato Casserole.

Make this, and you’ll use up 4 cups of mashed potatoes, so this might be the only leftover recipe you need (or, you can easily make a half batch of this if you have less leftovers).

It’s loaded with all the good stuff, like bacon, cheese, sour cream and two kinds of onions, and topped with crushed cheese crackers for good measure.

Mashed Potato Casserole Ingredients

• mashed potatoes – use whatever type of mashed potatoes you have on hand for this leftover mashed potato recipe. I usually make a double batch of mashed potatoes with heavy whipping cream for Thanksgiving, and use the leftovers here.
• sour cream – this adds some moisture back into the mashed potatoes, which tend to dry out when they’re heated up a second time.
• garlic powder – I normally use fresh garlic for just about everything, but I actually love the flavor of garlic powder in mashed potatoes!
• sharp cheddar cheese – because it’s not a loaded mashed potatoes recipe unless we add cheese! You can use any type of cheese you want.
• bacon – make a quick batch of bacon in the oven and crumble it up. Or, if turkey bacon is more your speed, check out my tutorials on how to cook turkey bacon in oven and turkey bacon in the air fryer!
• red onion – I add quite a bit of onion to this loaded mashed potato casserole for added flavor. You can also use white or yellow onion.
• green onion – yes, a second type of onion! I like to add these for color.
• parsley – this is mainly for color, but you can skip it if you don’t have any on hand.
• cheese crackers – I love adding crushed cheese crackers (like Cheez-Its or Goldfish) to the top of these baked loaded mashed potatoes for a bit of crunch. You can also use Ritz crackers or potato chips!
• butter – tossing the crackers in a bit of melted butter ensures they’ll get nice and golden brown on top of the casserole.

What Are The Top 3 Potatoes For Mashed Potatoes?

For ideal taste and texture, the best potatoes for mashed potatoes are Russet (my top choice), Idaho or Yukon Gold potatoes. The creamy and starchy consistency of these types of potatoes makes the smoothest, most velvety mashed potatoes.

How To Make Loaded Mashed Potato Casserole

1. PREP. Preheat the oven, spray a casserole dish with nonstick spray, and stir together the cheese crackers and melted butter to make the topping.

2. WARM AND MIX POTATOES. If your mashed potatoes are cold, microwave them briefly until they are just soft enough to stir again. Stir the sour cream, garlic powder and pepper into the mashed potatoes.

3. ADD THE MIX INS. Set aside 2 tablespoons each of bacon and cheese, then add the rest of the bacon and cheese, along with the red onion, green onion and parsley to the potatoes. Stir until everything is well combined.

4. CASSEROLE DISH. Transfer the potato mixture to the prepared baking dish and spread it into an even layer.

5. TOPPINGS. Sprinkle the potato mixture with the cracker mixture and the reserved bacon and cheese.

6. BAKE. Transfer the dish to the oven and bake 25 to 30 minutes or until everything is heated through.

How To Serve Mashed Potato Casserole

Serve this luscious casserole as a satisfying side dish to a main course any time of the year, or serve it alongside leftovers of your holiday entree. Some ideas include:

• Baby Back Ribs in Oven
• Bourbon Turkey
• Turkey Tenderloin Recipe
• Baked Ham with Pineapple
• Flat Iron Steak Recipe

How To Store Loaded Potato Casserole

If you make this mashed potato casserole with freshly-made mashed potatoes, you can cool any leftovers and then store them in an airtight container in the fridge for up to 3 days, or the freezer for up to 3 months.

However, if you make these loaded mashed potatoes using leftover mashed potatoes, I do NOT advise keeping them and reheating them again. 

As a general rule of thumb for food safety, you only want to reheat leftovers once. Anything left over after that, you should discard.

How To Reheat Mashed Potatoes

The easiest way to reheat leftover, plain mashed potatoes is to simply spread them in a buttered casserole dish, cover them with foil, and bake at 350 degrees F until they are completely heated through.

But why not add some extra flavor before you reheat? That’s where this loaded mashed potato casserole recipe comes in, allowing you to add a bunch of flavorful mix-ins before you reheat.

Loaded Mashed Potatoes Recipe FAQs