Description
This classic Au Gratin Potatoes recipe features thinly sliced Yukon Gold potatoes baked in a rich and creamy cheese sauce made with cheddar, gruyere, and parmesan. Tender potatoes layered with sautéed onions and a flavorful, cheesy béchamel sauce create the perfect decadent side dish for any holiday or special occasion meal.
Ingredients
Scale
Potatoes and Onion
- 3 lbs Yukon Gold potatoes (thinly sliced, about 12 potatoes)
- ½ yellow onion (thinly sliced)
Sauce
- 4 tbsp unsalted butter (½ stick, plus more for greasing the pan)
- 2 cloves garlic (minced)
- ¼ cup all-purpose flour
- 1½ cups whole milk
- 1 tsp kosher salt
- ½ tsp ground black pepper
- 1 cup freshly shredded cheddar cheese
- 1½ cups freshly shredded gruyere cheese (divided)
- ½ cup freshly grated Parmesan cheese
Instructions
- Preheat and prepare the pan: Preheat your oven to 350°F. Grease a 9×13-inch baking dish with butter to prevent sticking.
- Layer potatoes and onions: Arrange the thinly sliced potatoes and onions evenly in layers inside the greased baking dish. Set aside.
- Make the cheese sauce: In a medium saucepan over medium heat, melt 4 tablespoons of butter. Add the minced garlic and sauté until fragrant, about 1 minute.
- Add flour to form roux: Sprinkle the flour over the melted butter and garlic, whisking constantly until the mixture is smooth and the flour turns golden, about 1 minute.
- Incorporate milk: Slowly pour in the whole milk while whisking continuously to prevent lumps. Bring the sauce to a gentle simmer and thicken.
- Combine seasonings and cheeses: Remove the saucepan from heat. Whisk in the kosher salt, black pepper, shredded cheddar cheese, and ¾ cup of the shredded gruyere cheese until fully melted and smooth.
- Pour cheese sauce: Pour this cheesy sauce evenly over the layered potatoes and onions in the baking dish.
- Bake covered: Cover the baking dish with aluminum foil and bake in the preheated oven for 60 minutes, or until the potatoes are tender when pierced with a knife in the center.
- Add remaining cheeses and bake uncovered: Remove the foil and sprinkle the remaining ¾ cup gruyere and the ½ cup grated parmesan cheese evenly over the top. Bake uncovered for an additional 20 minutes until the cheese topping is melted and bubbly.
- Optional broil for browning: For a golden-brown cheese crust, broil the dish for 1-2 minutes watching carefully to avoid burning.
- Serve and garnish: Garnish with fresh herbs if desired and serve hot as a delicious side dish.
Notes
- Use Yukon Gold potatoes for the best creamy texture and flavor.
- Thin, even slices ensure even cooking and tenderness.
- Adjust seasoning to taste; adding a pinch of nutmeg to the sauce is a nice variation.
- Allow potatoes to rest for a few minutes after baking for easier serving.
- To make ahead, prepare through step 7 and refrigerate; bake covered until tender before adding cheeses and finishing.
- Substitute half-and-half for milk for a richer sauce if desired.
Nutrition
- Serving Size: 1 serving
- Calories: 413 kcal
- Sugar: 4 g
- Sodium: 698 mg
- Fat: 22 g
- Saturated Fat: 13 g
- Unsaturated Fat: 7 g
- Trans Fat: 0.2 g
- Carbohydrates: 37 g
- Fiber: 4 g
- Protein: 18 g
- Cholesterol: 67 mg
