mashed potato gratin

Ingredients

For the Mashed Potatoes:

• 3 pounds (about 1.4 kg) Russet or Yukon Gold potatoes , peeled and cut into 2-inch chunks
• 4 tablespoons unsalted butter , melted
• 4 ounces cream cheese , softened to room temperature
• 1/2 cup heavy cream (or half-and-half, warmed)
• 3 cloves garlic , minced
• 1 teaspoon kosher salt (plus more for boiling water)
• 1/2 teaspoon freshly ground black pepper
• 1/4 teaspoon freshly grated nutmeg (optional, for a subtle warmth)

For the Gratin Topping:

• 2 cups shredded Gruyère cheese (or a sharp white cheddar for a bolder flavor)
• 1/2 cup freshly grated Parmesan cheese
• 2 tablespoons unsalted butter , cut into small cubes
• 2 tablespoons fresh chives , finely chopped (for garnish)

Instructions

Step 1: Boil the Potatoes

1. Place the peeled and cubed potatoes into a large pot and cover them with cold water by at least an inch.
2. Generously salt the water.
3. Bring the pot to a boil over medium-high heat, then reduce the heat to medium-low so the water maintains a gentle simmer.
4. Cook for 15 to 20 minutes , or until the potatoes are easily pierced all the way through with a fork.

Step 2: Drain and Mash

1. Drain the potatoes thoroughly in a colander and return them to the warm pot. Let them sit for 2 minutes to allow any excess moisture to evaporate.
2. Using a potato masher or a ricer, mash the potatoes until smooth.
3. Stir in the melted butter, softened cream cheese, warmed heavy cream, minced garlic, kosher salt, black pepper, and nutmeg. Stir until completely incorporated, creamy, and fluffy. Taste and adjust seasoning if necessary.

Step 3: Preheat and Prep

1. Preheat your oven to 400°F (200°C) .
2. Lightly grease a 9×13-inch baking dish with butter or non-stick cooking spray.

Step 4: Assemble the Gratin

1. Transfer the prepared mashed potatoes into the greased baking dish and use a spatula or the back of a spoon to spread them into an even layer.
2. Fluff the top slightly with the fork to create ridges and peaks—these will crisp up wonderfully in the oven.
3. Sprinkle the shredded Gruyère and freshly grated Parmesan evenly across the entire surface of the potatoes.
4. Dot the top with the small cubes of remaining unsalted butter to help achieve a rich, golden crust.

Step 5: Bake to Golden Perfection

1. Place the baking dish in the preheated oven and bake uncovered for 25 to 30 minutes .
2. The gratin is done when the cheese is completely melted, bubbling around the edges, and the top is a deep golden brown. If you prefer a darker, blistered crust, switch your oven to broil for the final 2 to 3 minutes (watch closely so it does not burn).

Step 6: Rest and Serve

1. Remove the gratin from the oven and let it rest for 10 minutes before serving. This helps the layers set and makes serving cleaner.
2. Garnish with freshly chopped chives for a pop of color and freshness, then serve hot.

Nutrition

Calories: 380 kcal · Protein: 11g · Fat: 24g Saturated Fat: 14g · Carbohydrates: 32g Dietary · Saturated Fat: 14g Cholesterol: 70mg · Fiber: 3g · Sugar: 3g · Sodium: 480mg