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Mashed Potato Casserole with Thyme, Parmesan, and Crispy Panko Topping Recipe

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★★★★★

4.8 from 72 reviews

This Mashed Potato Casserole elevates classic mashed potatoes with a creamy blend of cream cheese, Parmesan, and infused milk, topped with a buttery, golden panko crust. Perfectly comforting and rich, it’s an ideal side dish for holiday dinners or any cozy meal.

Ingredients

Scale

Milk Mixture

  • 1 cup whole milk
  • 6 sprigs thyme
  • 2 dried bay leaves
  • 4 tablespoons (1/2 stick) unsalted butter
  • 1/2 teaspoon kosher salt
  • 1/4 teaspoon freshly ground black pepper

Potatoes and Mix-ins

  • 4 pounds Yukon gold potatoes, peeled and cut into 1-inch pieces
  • 3 cloves garlic, smashed and peeled
  • 8 ounces cream cheese, room temperature
  • 1/2 cup finely grated Parmesan (about 2 oz.), divided
  • 2 large eggs, beaten to blend
  • Additional kosher salt and freshly ground black pepper, to taste

Topping

  • 2 tablespoons (1/4 stick) unsalted butter
  • 1 cup panko bread crumbs
  • 1/4 cup finely grated Parmesan (remaining portion)
  • Sliced chives, for serving

Instructions

  1. Infuse the Milk: In a medium saucepan over medium heat, combine milk, thyme sprigs, bay leaves, 4 tablespoons butter, 1/2 teaspoon salt, and 1/4 teaspoon pepper. Bring mixture to a gentle simmer, then remove from heat, cover, and let it steep for 1 hour to infuse the flavors.
  2. Prepare the Baking Dish: Preheat your oven to 375°F (190°C). Generously butter a 2.5- to 3-quart baking dish to prevent sticking and ensure an easy release after baking.
  3. Cook the Potatoes and Garlic: In a large pot, place the peeled and chopped potatoes along with the smashed garlic cloves. Cover with water by at least 2 inches, season the water with 2 tablespoons kosher salt, and bring it to a boil. Cook until the potatoes are fork-tender, about 12 to 15 minutes.
  4. Mash the Potatoes: Before draining, reserve 3/4 cup of the cooking liquid for later use. Drain the potatoes and garlic, then return them to the pot. Mash the potatoes and garlic smoothly using a potato masher.
  5. Finish the Potato Mixture: Return the infused milk to a bare simmer over medium heat; remove and discard the thyme sprigs and bay leaves. Stir in the cream cheese and 1/4 cup Parmesan into the milk until fully melted and smooth. Pour this creamy mixture into the mashed potatoes, add the beaten eggs, and mix thoroughly. Adjust the consistency with the reserved cooking liquid to reach a thick but spreadable texture. Season well with salt and pepper.
  6. Prepare the Topping: In a small skillet over medium heat, melt the remaining 2 tablespoons of butter. Cook the butter, swirling the pan, until it turns golden brown and emits a nutty aroma, about 2 to 3 minutes. Remove from heat, then stir in the panko bread crumbs and the remaining 1/4 cup Parmesan. Season with salt and pepper to taste.
  7. Assemble and Bake: Spread the mashed potato mixture into the prepared baking dish. Evenly sprinkle the browned butter-panko topping over the potatoes. Cover the dish with foil.
  8. Bake the Casserole: Place the casserole in the oven and bake covered for 10 minutes. Then remove the foil and continue baking until the casserole is thoroughly heated and the topping becomes golden brown and crisp, about 20 to 22 more minutes.
  9. Garnish and Serve: Once baked, garnish with freshly sliced chives to add a fresh, mild onion flavor and a pop of color. Serve hot.

Notes

  • If you prefer a richer flavor, consider using half-and-half or heavy cream instead of whole milk, but adjust the fat content in nutrition accordingly.
  • For a gluten-free version, substitute panko bread crumbs with gluten-free bread crumbs or crushed gluten-free crackers.
  • Allow the casserole to rest for 5 minutes after baking for easier serving.
  • Leftovers can be stored covered in the refrigerator for up to 3 days and reheated in the oven to maintain crispiness of the topping.
  • Ensure the cream cheese is at room temperature to blend smoothly into the milk infusion.

Keywords: mashed potato casserole, creamy mashed potatoes, cheesy potato bake, buttery panko topping, Yukon gold potatoes, comfort food side dish

Find it online: https://spatulaqueen.com/mashed-potato-casserole-with-thyme-parmesan-and-crispy-panko-topping-recipe/