Loaded Mashed Potato Casserole

5 from 1 vote

Loaded Mashed Potato Casserole

When it comes to comfort food side dishes, nothing beats a rich and cheesy loaded mashed potato casserole. This recipe takes tender russet potatoes, crispy bacon, melty cheddar, cream cheese, and Boursin garlic & herb cheese to create the ultimate holiday or weeknight side.

Prep Time15

Cook Time30

Total Time45

Course: Appetizer, Comfort Food, Side Dish

Cuisine: American

Servings: servings

Author: Matt Price

Equipment

Large Pot
Skillet
Potato Masher
9x11 Casserole Dish
Box Grater
Sharp Knife

Ingredients

4 medium russet potatoes
6-7 strips thick-cut bacon
1 cup yellow cheddar shredded
1 cup white cheddar shredded
½ package Boursin garlic & herb cheese
3 green onions whites for cooking, greens for garnish
½ diced yellow onion
4 oz cream cheese room temperature
1 tablespoon garlic fresh or paste
3 tablespoon butter
1 cup whole milk or half & half/heavy cream
Salt pepper, garlic powder, onion powder (to taste)

Instructions

Step 1: Prep the Potatoes

Wash and peel 4 medium russet potatoes, then cut them into even bite-sized chunks so they cook evenly.
Rinse the pieces several times in cold water until it runs clear—this removes excess starch for fluffier mashed potatoes.
Add potatoes to a large pot, cover with water, season with 1 tablespoon kosher salt, and bring to a boil.
Cook until fork-tender, about 12–15 minutes. Drain well.

Step 2: Crisp the Bacon

While the potatoes are boiling, arrange 6–7 strips of thick-cut bacon on a foil-lined baking sheet.
Bake at 425°F until crispy (about 12–15 minutes). Once done, transfer to a paper towel–lined plate and chop into bite-sized pieces. Reserve some for topping.

Step 3: Grate the Cheese

While the bacon cooks, shred 1 cup yellow cheddar and 1 cup white cheddar using a box grater.
Freshly grated cheese melts more smoothly and gives the casserole a creamier texture than pre-shredded cheese.

Step 4: Sauté the Onions & Garlic

In a skillet, heat 1–2 tablespoon bacon fat (or butter if preferred) over medium heat.
Add ½ diced yellow onion and the whites of 3 green onions, sautéing until soft and fragrant (about 3 minutes).
Stir in 1 tablespoon garlic and cook for 1 more minute. Set aside.

Step 5: Mash the Potatoes

In the same pot you boiled them in, mash the hot potatoes with a handheld masher.
Mix in: 4 oz cream cheese (softened), ½ package Boursin garlic & herb cheese, 3 tablespoon butter, 1 cup whole milk (add gradually until creamy), Stir until smooth and fluffy.

Step 6: Load It Up

Fold in the sautéed onions, half the bacon, and half the shredded cheese.
Taste and season with salt, pepper, garlic powder, and onion powder as needed.

Step 7: Bake the Casserole

Transfer mashed potato mixture into a 9x11 casserole dish.
Spread evenly, then top with the remaining cheddar cheese.
Bake at 375°F for 20 minutes until the cheese is bubbly and golden.

Step 8: Garnish & Serve

Once baked, let the casserole rest for 10 minutes.
Top with the remaining crispy bacon, chopped green onion tops, and an extra sprinkle of cheddar if you like things extra cheesy.
Serve hot with your favorite main dish!

Notes

Pro Tips for the Best Loaded Potato Casserole

Don’t skip salting the water – this seasons the potatoes from within.
Room temp cream cheese mixes smoother than cold.
Make ahead: Assemble the casserole up to the baking step, refrigerate, then bake when ready to serve.
Mix up your cheese: Try pepper jack, gouda, or mozzarella for new flavor twists.

Serving Ideas

This cheesy potato casserole pairs perfectly with:

Glazed ham, roasted turkey, or grilled steak
Green beans, roasted broccoli, or Caesar salad
A crisp Chardonnay or sparkling cider

Nutrition