There’s something undeniably comforting about a bubbling dish of creamy au gratin potatoes fresh from the oven. This is our favorite Easter side-dish.
Thinly sliced russet potatoes are layered with tender onions and blanketed in a rich, velvety cheese sauce that bakes into golden, irresistible perfection.
Each bite delivers a balance of soft, melt-in-your-mouth potatoes and savory, cheesy goodness.
This classic casserole is perfect for both everyday dinners and special occasions, pairing beautifully with roasted meats or a simple green salad.
It’s a timeless side dish that feels indulgent yet approachable, making it a reliable favorite whenever you want something warm, hearty, and satisfying.
Prep Time: 30 mins
Cook Time: 1 hr 30 mins
Total Time: 2 hrs
Servings: 4
Yield: 1 (2-quart) casserole
Ingredients
- 4 medium russet potatoes, thinly sliced
- 1 medium onion, sliced into rings
- Salt and ground black pepper, to taste
- 3 tablespoons butter
- 3 tablespoons all-purpose flour
- 1/2 teaspoon salt
- 2 cups milk
- 1 1/2 cups shredded Cheddar cheese
Directions
- Preheat oven to 400°F (200°C). Lightly grease a 2-quart casserole dish with butter.
- Arrange half of the sliced potatoes in an even layer in the prepared dish. Season with salt and pepper.
- Spread the onion rings evenly over the potatoes, then layer the remaining potatoes on top. Season again with salt and pepper.
- In a medium saucepan over medium heat, melt the butter. Whisk in the flour and salt, cooking for about 1 minute until the raw flour taste is gone.
- Gradually whisk in the milk, adding a little at a time and stirring well to keep the sauce smooth and lump-free.
- Continue cooking, whisking constantly, until the sauce thickens, about 3 to 5 minutes.
- Add the shredded cheese and stir until fully melted and smooth.
- Pour the cheese sauce evenly over the layered potatoes. Cover the dish with aluminum foil.
- Bake for about 1 1/2 hours, or until the potatoes are tender and the sauce is bubbling.
Chefs Notes
- For deeper flavor, try swapping part of the Cheddar with Gruyère or Swiss cheese.
- Slice potatoes evenly for consistent cooking throughout the dish.
- For a golden top, remove the foil during the last 10–15 minutes of baking.
- Pairs perfectly with roast pork loin, beef tenderloin, or a simple green salad.