Description
This classic Au Gratin Potatoes recipe features thinly sliced Yukon Gold potatoes baked in a creamy cheese sauce with layers of yellow onion and garlic, topped with a blend of cheddar, gruyere, and Parmesan cheeses. Perfectly tender and rich, this comforting side dish is ideal for holiday dinners or any special occasion.
Ingredients
Scale
Potatoes and Vegetables
- 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
Cheeses
- 1 cup freshly shredded cheddar cheese
- 1½ cups freshly shredded gruyere cheese (divided)
- ½ cup freshly grated Parmesan cheese
Instructions
- Preheat and Prepare 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 yellow onions evenly in the prepared baking dish. Set aside while you prepare the sauce.
- Make the Cheese Sauce: In a medium saucepan over medium heat, melt 4 tablespoons of butter. Add the minced garlic and cook until fragrant, about 1 minute, being careful not to burn it.
- Add Flour: Sprinkle the all-purpose flour over the melted butter and garlic, whisking continuously until the mixture is smooth and the flour turns a light golden color, about 1 minute.
- Add Milk: Slowly pour in the whole milk while whisking steadily to prevent lumps. Bring the sauce to a gentle simmer, stirring frequently until it thickens slightly.
- Add Seasoning and Cheese: Remove the sauce from heat and whisk in the kosher salt, ground black pepper, shredded cheddar cheese, and ¾ cup of the shredded gruyere cheese until the cheeses are fully melted and the sauce is smooth.
- Pour Sauce Over Potatoes: Carefully pour the warm cheese sauce evenly over the layered potatoes and onions in the baking dish.
- Bake Covered: Cover the dish tightly with aluminum foil and bake in the preheated oven for 60 minutes, or until the potatoes are tender when pierced with a knife.
- Add Remaining Cheese and Finish Baking: Remove the foil and sprinkle the remaining ¾ cup gruyere and the grated Parmesan cheese evenly over the top. Return to the oven and bake uncovered for an additional 20 minutes until the cheese is melted, bubbly, and lightly golden.
- Optional Broil: For a nicely browned and crispy cheese topping, broil the potatoes for 1-2 minutes, watching carefully to avoid burning.
- Garnish and Serve: Let the dish rest for a few minutes, garnish with fresh herbs if desired, and serve warm as a decadent side dish.
Notes
- Use Yukon Gold potatoes for their creamy texture and ability to hold shape during baking.
- Thinly slice potatoes uniformly to ensure even cooking.
- You can substitute whole milk with 2% milk for a slightly lighter dish, though whole milk provides richer flavor.
- If you prefer a stronger cheese flavor, increase the amount of cheddar or gruyere slightly.
- Broiling at the end is optional but recommended for a golden, crispy cheese topping.
- This dish pairs beautifully with roasted meats or a fresh green salad for a balanced meal.
- For easier slicing, you can use a mandoline slicer but be cautious to slice evenly and safely.
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
