Creamy au Gratin Potatoes
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
- ½ teaspoon salt
- 2 cups milk
- 1 ½ cups shredded Cheddar cheese
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Instructions
- Gather all ingredients. Preheat the oven to 400 degrees F (200 degrees C). Grease a 2-quart casserole dish with butter.
- Layer 1/2 of the potatoes in the bottom of the prepared casserole dish; season with salt and pepper.
- Layer onion slices over top, then top with with remaining potatoes. Season again with salt and pepper.
- Melt butter in a medium saucepan over medium heat. Whisk in flour and salt; cook, whisking constantly, until raw flour flavor has cooked off, about 1 minute.
- Gradually add milk, about 1/4 cup at a time, whisking well after each addition to incorporate; the gradual addition and whisking of milk will help avoid lumps in your sauce.
- Cook, whisking constantly, until the mixture has thickened, 3 to 5 minutes.
- Stir in cheese all at once; cook, stirring constantly, until melted, 30 to 60 seconds.
- Pour cheese sauce over the potatoes, and cover the dish with aluminum foil.
- Bake in the preheated oven until potatoes are tender and sauce is bubbly, about 1 ½ hours.
Source
Original recipe: View Original