Description
Classic Au Gratin Potatoes made with thinly sliced Yukon Gold potatoes layered with onions and baked in a rich and creamy cheese sauce featuring cheddar, gruyere, and parmesan cheeses. This comforting side dish is perfect for holiday dinners or any special occasion.
Ingredients
Scale
Potatoes and Onions
- 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: Preheat your oven to 350°F and grease a 9×13-inch baking pan with butter to prevent sticking.
- Layer Potatoes and Onions: Arrange the thinly sliced potatoes and onions in layers inside the prepared baking dish. Set aside while making the sauce.
- Make the Roux: In a medium saucepan over medium heat, melt the butter. Add the minced garlic and cook until fragrant, about 1 minute, being careful not to burn it.
- Add Flour: Sprinkle the flour over the butter and garlic mixture and whisk continuously until the mixture is smooth and the flour turns a golden color, approximately 1 minute.
- Add Milk: Slowly pour in the milk while whisking constantly to avoid lumps. Continue whisking and bring the mixture to a simmer to thicken the sauce.
- Incorporate Seasoning and Cheese: Remove the saucepan from heat and whisk in the kosher salt, black pepper, cheddar cheese, and ¾ cup of the grated gruyere cheese until completely melted and smooth.
- Combine Sauce with Potatoes: Pour the cheese sauce evenly over the layered potatoes and onions in the baking dish.
- Bake Covered: Cover the dish tightly with aluminum foil and bake for 60 minutes, or until the potatoes are tender when pierced with a knife in the center.
- Add Remaining Cheese and Finish Baking: Remove the foil and sprinkle the remaining ¾ cup of gruyere and the parmesan cheese evenly over the top. Bake uncovered for an additional 20 minutes until the cheese is melted and bubbly.
- Optional Broiling: For a golden brown cheese crust, broil the dish for 1-2 minutes, watching carefully to prevent burning.
- Serve: Garnish with fresh herbs if desired and serve hot as a delicious side dish.
Notes
- Use Yukon Gold potatoes for their creamy texture and ability to hold shape well when baked.
- For a sharper flavor, substitute part of the cheddar with aged cheddar or add a bit of smoked cheese.
- Make sure to slice the potatoes uniformly thin for even cooking.
- You can prepare this dish a few hours ahead and refrigerate; bake covered and add extra baking time if baking from chilled.
- Leftovers can be reheated in the oven to maintain crispiness rather than in a microwave.
- To make this dish gluten-free, substitute all-purpose flour with a gluten-free flour blend or cornstarch (use half the amount).
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
