Description
Potatoes au Gratin is a rich, creamy, and cheesy baked potato dish featuring thinly sliced russet potatoes layered with a savory blend of sharp cheddar and Gruyère cheeses, all enveloped in a luxurious cream sauce. This classic French-inspired side dish is perfect for holiday dinners or comforting everyday meals.
Ingredients
Scale
Potatoes
- 4 large russet potatoes, peeled and thinly sliced
Cream Sauce
- 2 cups heavy cream
- 1 cup whole milk
- 2 cloves garlic, minced
- 2 tablespoons unsalted butter
- 1 tablespoon all-purpose flour
- 1/2 teaspoon salt (or to taste)
- 1/4 teaspoon black pepper (or to taste)
- 1/4 teaspoon ground nutmeg (optional)
Cheeses
- 2 cups sharp cheddar cheese, shredded
- 1 cup Gruyère cheese, shredded (optional, for extra flavor)
- 1/2 cup grated Parmesan cheese (for topping)
Garnish
- Fresh parsley, chopped (optional)
Instructions
- Preheat the oven: Preheat your oven to 375°F (190°C) and grease a 9×13-inch baking dish with butter or non-stick spray to prevent sticking.
- Prepare the potatoes: Peel and thinly slice the russet potatoes to about 1/8-inch thickness, preferably using a mandoline slicer for consistent thinness. Set the slices aside.
- Make the creamy sauce – melt butter and cook garlic: In a medium saucepan over medium heat, melt the butter, then add the minced garlic and cook for about 1 minute until fragrant but not browned.
- Make a roux: Stir in the all-purpose flour and continuously whisk for about 1 minute to form a smooth paste and cook off the raw flour taste.
- Add cream and milk: Gradually whisk in the heavy cream and whole milk while stirring constantly to avoid lumps. Continue cooking and stirring occasionally until the sauce thickens, about 4 to 5 minutes.
- Season and add cheese: Remove from heat and stir in salt, pepper, and optional nutmeg. Then add the shredded cheddar and Gruyère cheese, stirring until melted and the sauce is smooth.
- Assemble the gratin – first layer: Place half of the sliced potatoes in the bottom of the prepared baking dish and pour half of the cheese sauce over the potatoes, spreading it evenly.
- Assemble the gratin – second layer: Layer the remaining sliced potatoes on top and pour the remaining cheese sauce over this second layer, spreading it to cover evenly.
- Bake covered: Cover the dish tightly with aluminum foil and bake in the preheated oven for 40 minutes to allow potatoes to cook through and sauce to meld.
- Add Parmesan and bake uncovered: Remove the foil, sprinkle grated Parmesan cheese evenly on top, then continue baking uncovered for an additional 20 to 25 minutes until the top is golden brown and the potatoes are tender when pierced with a fork.
- Rest and garnish: Let the potatoes au gratin rest for about 5 minutes to set. Garnish with chopped fresh parsley if desired.
- Serve: Serve hot as a delicious side dish alongside your favorite main courses.
Notes
- Use a mandoline slicer for evenly thin potato slices to ensure even cooking.
- Gruyère cheese is optional but adds a lovely depth of flavor; you can omit or substitute with more cheddar if desired.
- Adjust salt and pepper to taste, especially if using salted butter or cheeses with varying salt content.
- Allowing the dish to rest before serving lets the sauce thicken slightly for cleaner slicing and plating.
- For a crispier top, you can broil uncovered for 2-3 minutes at the end of baking, watching carefully to avoid burning.
