Au gratin potatoes made with thinly sliced potatoes and onions baked in a decadently rich and creamy Cheddar cheese sauce until tender and bubbling.
Step1
Preheat the oven to 400 degrees F (200 degrees C). Butter a 1-quart casserole dish.
Step2
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.
Step3
Melt butter in a medium saucepan over medium heat. Gradually whisk in flour and salt and 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.
Step4
Cook, whisking constantly, until the mixture has thickened, 3 to 5 minutes. Stir in cheese all at once; continue stirring until melted, 30 to 60 seconds. Pour cheese sauce over the potatoes, and cover the dish with aluminum foil.
Step5
Bake in the preheated oven until potatoes are tender and sauce is bubbly, about 1 1/2 hours.
Prepare Time:
30 mins
Cook Time:
1 hours 30
Total Time:
2 hours 0
Servings:
4
Calories:
499 kcal
Carbohydrate:
49 g
Cholesterol:
77 mg
Dietary Fiber:
4 g
Protein:
20 g
Saturated Fat:
16 g
Sodium:
683 mg
Total Sugars:
9 g
Total Fat:
25 g
