Description
Tender russet potato and onion slices baked in a rich, smooth cheddar sauce until creamy inside and golden on top.
Ingredients
Scale
- 4 medium russet potatoes, about 2 pounds, peeled and sliced ¼ inch thick
- 1 yellow onion, sliced into thin rings
- 3 tablespoons unsalted butter
- 3 tablespoons all-purpose flour
- ½ teaspoon kosher salt
- 2 cups whole milk, room temperature
- 1½ cups mild cheddar cheese, freshly shredded
- Salt, to taste
- Freshly ground black pepper, to taste
- Nonstick cooking spray, for the baking dish
Instructions
- Preheat the oven to 400°F. Lightly coat an 8-inch square or 2-quart baking dish with nonstick cooking spray.
- Arrange the sliced potatoes and onion rings in the prepared baking dish, alternating and slightly overlapping the slices.
- Melt the butter in a medium saucepan over medium heat.
- Add the flour and kosher salt, then whisk constantly for 1 minute.
- Slowly pour in the milk while whisking. Continue cooking until the sauce thickens and lightly coats the back of a spoon.
- Add the shredded cheddar and stir for 30 to 60 seconds, or until completely melted and smooth.
- Pour the cheese sauce evenly over the potatoes and onions.
- Cover the baking dish tightly with aluminum foil.
- Bake for 85 to 90 minutes, or until a thin knife slides easily through the potatoes.
- Remove the foil. Switch the oven to broil and broil briefly until the top turns golden brown.
- Season with additional salt and black pepper to taste.
- Let the casserole rest for 10 minutes before serving.
Notes
- Slice the potatoes evenly so every layer cooks at the same rate.
- Freshly shredded cheese produces a smoother sauce than packaged shredded cheese.
- Watch the casserole closely while broiling because the cheese can brown quickly.
- Store covered leftovers in the refrigerator for up to 4 days.
- Reheat covered at 350°F, adding a small splash of milk if the sauce appears too thick.
- Prep Time: 15 minutes
- Cook Time: 1 hour 30 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1/8 casserole
- Calories: 346
- Sugar: 6
- Sodium: 350
- Fat: 16
- Saturated Fat: 10
- Unsaturated Fat: 5
- Trans Fat: 0
- Carbohydrates: 43
- Fiber: 3
- Protein: 10
- Cholesterol: 47