Au Gratin Potatoes Recipe
Golden, cheesy, and irresistibly creamy, these au gratin potatoes are the ultimate comfort food. Thinly sliced potatoes are layered with onions, bathed in a velvety cheese sauce, and baked to bubbly perfection. Perfect for holidays or weeknight dinners, this dish pairs beautifully with roasted meats or vegetables.
Prep Time 30 minutes mins
Cook Time 1 hour hr 30 minutes mins
Total Time 2 hours hrs
Course Side Dish
Cuisine French
Servings 4 people
Calories 499 kcal
- salt and ground black pepper to taste
- 4 medium russet potatoes, thinly sliced
- 2 cups milk
- 3 tbsp butter
- 1 medium onion, sliced into rings
- 1½ cups shredded Cheddar cheese
- 3 tbsp all-purpose flour
- ½ tsp salt
Preheat the oven to 400°F (200°C) and butter a 2-quart casserole dish.
Arrange half of the sliced potatoes in the dish, season with salt and pepper, then layer the onion slices on top.
Add the remaining potatoes and season again.
In a saucepan over medium heat, melt the butter, whisk in flour and salt, and cook for about a minute until the raw flour taste is gone.
Slowly add milk, about ¼ cup at a time, whisking constantly to prevent lumps.
Cook until thickened, 3 to 5 minutes, then stir in the cheese until fully melted.
Pour the cheese sauce over the layered potatoes, ensuring even coverage.
Cover with aluminum foil and bake for about 1 ½ hours, until the potatoes are tender and the sauce is bubbling.
Serve hot and enjoy.
- For even cooking, slice the potatoes no thicker than ¼ inch. A mandoline slicer ensures uniform slices.
- For extra richness, substitute half of the milk with heavy cream.
- Try using a mix of cheeses, like Gruyère and sharp cheddar, for added depth of flavor.