Mashed potato casserole is the ultimate holiday side dish you’ve been waiting for. It’s bound to find its way onto your holiday dinner table at some point during the season, but it makes a great side dish any time of the year because it’s creamy, fluffy, and oh-so-cheesy. Here’s what to know:

How To Make Mashed Potato Casserole

INGREDIENTS

  • Potatoes: We use Yukon gold potatoes instead of the typical russets. Yukon golds are creamier and slightly less starchy, and make the most silky smooth mashed potatoes you can get.
  • Milk: The fat content in whole milk is just what you need to add richness, creaminess, and flavor to your casserole.
  • Cream Cheese: The tanginess will round out the buttery potatoes and thicken up your whole casserole.
  • Butter: We call for unsalted butter here, but if you want to add salted, then just be careful about not oversalting your casserole!
  • Eggs: These are stirred in before baking to lighten up the potatoes, and they help the mixture “soufflé” a bit in the oven. Since the eggs in this recipe add some richness to the dish, we use a little less milk than we normally would for mashed potatoes.
  • Panko Bread Crumbs: The best part of this dish is the topping. Crunchy panko bread crumbs are tossed with Parmesan cheese and nutty brown butter and sprinkled over the top before baking. It becomes crispy and golden in the oven, which complements the creaminess of the potatoes very well.
  • Herbs: We opt for fresh thyme and bay leaves, but sage, rosemary, or fresh oregano would all be great additions.
  • Garlic: Flavor alert! Feel free to skip if you like, but this is one of the best parts of this recipe.

STEP-BY-STEP INSTRUCTIONS

Start with a medium saucepan over medium heat, and bring milk, thyme, bay leaves, 4 tablespoons butter, 1/2 teaspoon salt, and 1/4 teaspoon pepper to a simmer, just enough for the herby milk to start bubbling but not fully boiling (you don’t want to burn the milk!). Remove from heat, cover, and let stand 1 hour at room temperature.

Preheat oven to 375°. Grease a 2 1/2- to 3-quart baking dish with butter. In a large pot, combine potatoes and garlic. Cover with at least 2 inches of water and season with 2 tablespoons of salt. Bring this to a boil and cook until tender, 12 to 15 minutes. You’ll know they are done when you can stick a fork in them easily. Reserve 3/4 cup cooking liquid, then drain. Return potatoes and garlic to the pot and mash with a potato masher until smooth.

Meanwhile, return infused milk to a bare simmer over medium heat; discard thyme and bay leaves. Add cream cheese and 1/4 cup Parmesan and stir until smooth and melted. Add to mashed potatoes along with eggs. If needed, gradually add reserved cooking liquid until consistency is thick but spreadable; season with salt and pepper. Transfer mixture to the prepared dish.

In a small skillet over medium heat, melt the remaining 2 tablespoons of butter. Cook, swirling the pan, until butter begins to brown and smell nutty, 2 to 3 minutes. Remove from heat and stir in panko and remaining 1/4 cup Parmesan; season with salt and pepper. Sprinkle over the mashed potato mixture. Cover the pan with foil.

Bake the casserole for 10 minutes. Uncover and continue to bake until hot and the topping is golden brown, about 20 to 22 minutes. Top with chives and serve.

Full list of ingredients and directions can be found in the recipe below.

    Make Ahead & Storage

    If you want to make this recipe ahead, keep the bread-crumb topping separate until just before baking and refrigerate it for up to 1 day. On the day of, proceed with the recipe, but expect about 20 more minutes of baking time.

    Made this? Let us know how it went in the comments below.