The Ultimate Cheesy Scalloped Potatoes
A foolproof recipe for the creamiest, most decadent Cheesy Scalloped Potatoes, with tips for the perfect golden-brown top and a velvety sauce every time.
Ingredients
For the Potato Layers:
- 3 pounds Russet potatoes peeled and thinly sliced {1.36 kg}
- 1 medium yellow onion thinly sliced
For the Cheesy Sauce:
- 4 tablespoons unsalted butter {57 grams}
- 1/4 cup all-purpose flour {30 grams}
- 2 1/2 cups whole milk {590 ml}
- 1 cup vegetable or chicken broth {240 ml}
- 2 teaspoons kosher salt
- 1/2 teaspoon black pepper
- 1/4 teaspoon freshly grated nutmeg
For Assembly:
- 2 cups freshly shredded sharp cheddar cheese {8 oz / 225 grams}
- 1/2 cup freshly shredded Gruyère cheese {2 oz / 55 grams}
Instructions
Step 1: Prep. Preheat oven to 375°F (190°C). Butter a 9x13 inch baking dish. Slice potatoes 1/8-inch thick and submerge in cold water.
Step 2: Make the Sauce. Melt butter in a saucepan. Cook onions until soft. Sprinkle flour over onions and cook for 1-2 minutes, stirring. Gradually whisk in milk, then broth, until smooth. Cook until thickened. Remove from heat, season with salt, pepper, and nutmeg.
Step 3: Assemble. Drain and pat potatoes dry. Spread a thin layer of sauce in the dish. Layer half the potatoes, half the remaining sauce, and all of the Gruyère and 1 cup cheddar. Repeat with remaining potatoes and sauce.
Step 4: Bake. Top with remaining 1 cup cheddar. Cover tightly with foil and bake for 40 minutes. Uncover and bake for 25-35 more minutes until golden, bubbly, and potatoes are tender. Let rest for 15 minutes before serving.
Notes
For best results, shred cheese from a block and slice potatoes evenly. Letting the dish rest is crucial for the sauce to set. Leftovers can be stored in the fridge for 3-4 days. Reheat in the oven for best texture.