Duchess Potato Casserole

• servings: 10 servings

Ingredients

3 1/2 pounds, Yukon Gold potatoes, peeled and sliced 1/2 inch thick

2/3 cup, half-and-half

1 , large egg, separated, plus 2 large yolks

, Salt and pepper

Pinch, nutmeg

10 tablespoons, unsalted butter, melted

Directions

Recipe Instructions

Freshly ground nutmeg contributes heady flavor, so be sure to use it sparingly.

Adjust oven rack to middle position and heat oven to 450 degrees. Grease 13 by 9-inch baking dish. Place potatoes in large saucepan and add cold water to cover by 1 inch. Bring to simmer over medium-high heat. Adjust heat to maintain gentle simmer and cook until paring knife can be slipped into and out of centers of potatoes with no resistance, 18 to 22 minutes. Drain potatoes.

While potatoes cook, combine half-and-half, 3 egg yolks, 1 3/4 teaspoons salt, 1/2 teaspoon pepper, and nutmeg in bowl. Set aside.

Place now-empty saucepan over low heat; set ricer or food mill over saucepan. Working in batches, transfer potatoes to hopper and process. Using rubber spatula, stir in 8 tablespoons melted butter until incorporated. Stir in reserved half-and-half mixture until combined. Transfer potatoes to prepared dish and smooth into even layer.

Combine egg white, remaining 2 tablespoons melted butter, and pinch salt in bowl and beat with fork until combined. Pour egg white mixture over potatoes, tilting dish so mixture evenly covers surface. Using flat side of paring knife, make series of 1/2-inch-deep, 1/4-inch-wide parallel grooves across surface of casserole. Make second series of parallel grooves across surface, at angle to first series, to create crosshatch pattern. Bake casserole until golden brown, 25 to 30 minutes, rotating dish halfway through baking. Let cool for 20 minutes. Serve.

TO MAKE AHEAD: At end of step 3, wrap dish in plastic wrap and refrigerate for up to 24 hours. To serve, top and score casserole as directed in step 4 and bake in 375-degree oven for 45 to 50 minutes.

Test Kitchen Techniques

Nutrition

• Calories: 254
• Total Fat: 14 g
• Saturated Fat: 9 g
• Unsaturated Fat: 4 g
• Trans Fat: 0 g
• Cholesterol: 55 miligrams
• Sodium: 453 miligrams
• Total Carbohydrate: 25 g
• Total Sugars: 2 g
• Protein: 5 g