Description
This rich and indulgent au gratin potatoes dish features layers of tender Yukon Gold potatoes, savory onion slices, and a creamy cheese sauce made with cheddar, Gruyere, and Parmesan. Perfect for holidays or as a comforting side dish for any occasion!
Ingredients
Scale
Potatoes & Onions
- 6–7 medium Yukon Gold potatoes (3 lbs), thinly sliced into 1/8-inch rounds
- ½ white or yellow onion, sliced
Cheese Sauce
- 2 tablespoons salted butter
- ¼ cup all-purpose flour (or gluten-free 1:1 flour)
- 1½ cups unsweetened almond milk (or regular/whole milk)
- 8 ounces sharp cheddar cheese (about 2 heaping cups, shredded)
- ½ teaspoon garlic powder
- ¾ teaspoon salt (plus more to taste)
- Freshly ground black pepper, to taste
Topping
- ½ cup Gruyere cheese (or substitute with more sharp cheddar)
- ¼ cup grated Parmesan cheese
Garnish
- Fresh chopped parsley
Instructions
- Preheat the Oven: Preheat to 375°F. Grease a 2-quart square baking dish or an 8×12-inch pan with nonstick spray, butter, or oil.
- Layer the Potatoes & Onions: Arrange the potato slices in three slanted rows, leaving slight gaps between them. Add onion slices between and on top of the potato layers.
- Prepare the Cheese Sauce: In a medium saucepan, melt butter over medium heat. Gradually whisk in the flour, alternating with the milk, to create a smooth mixture. Bring to a simmer, whisking constantly until the sauce reaches a gravy-like consistency. Reduce the heat to low and stir in shredded cheddar cheese, garlic powder, salt, and pepper. Taste and adjust seasoning as needed.
- Assemble the Dish: Pour the cheese sauce evenly over the potatoes and onions, ensuring the layers are well-coated.
- Bake: Cover the dish with foil and bake for 45 minutes.
- Add Toppings & Finish Baking: Remove the foil, sprinkle Gruyere (or additional cheddar) and Parmesan over the top, and bake uncovered for another 30–45 minutes. The dish is ready when the potatoes are tender (easily pierced with a fork) and the top is golden brown.
- Garnish & Serve: Remove from the oven, garnish with fresh chopped parsley, and serve hot.
Notes
- If you prefer, you can make this dish ahead of time by assembling it and storing it in the fridge for up to 24 hours before baking.
- Feel free to substitute regular milk for almond milk if you prefer.
- You can replace Gruyere with more sharp cheddar if preferred.
- The dish can be easily doubled for larger gatherings or holiday meals.
- Ensure the potatoes are sliced thinly and evenly for consistent cooking.
- Prep Time: 30 minutes
- Cook Time: 1 hour 15 minutes
- Category: Side Dish
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 serving
- Calories: 320 kcal
- Sugar: 2g
- Sodium: 550mg
- Fat: 20g
- Saturated Fat: 12g
- Unsaturated Fat: 6g
- Trans Fat: 0g
- Carbohydrates: 30g
- Fiber: 3g
- Protein: 10g
- Cholesterol: 45mg