Description
This recipe elevates the classic au gratin potatoes with layers of flavor and richness, making them the perfect side dish for any occasion. These potatoes are tender, cheesy, and utterly irresistible.
Ingredients
2 ½ pounds Yukon gold potatoes (6 to 7 medium potatoes), sliced into ⅛-inch-thick rounds
½ medium yellow onion, thinly sliced
Sauce:
3 tablespoons salted butter
¼ cup all-purpose flour
1 ½ cups whole milk or unsweetened almond milk
8 ounces sharp Cheddar cheese (2 cups)
¾ teaspoon kosher salt, plus more to taste
½ teaspoon garlic powder
Freshly ground black pepper
Toppings:
2 ounces shredded Gruyere cheese (½ cup)
2 ounces grated Parmesan cheese (½ cup)
Chopped fresh chives or parsley
Instructions
Preheat the oven to 375F and lightly spray a 9-inch square baking dish with cooking spray. Arrange potato slices in rows, with onion slices in between.
Make the sauce by melting butter, whisking in flour, and slowly adding milk until smooth and combined. Bring to a boil, then simmer until thickened. Stir in Cheddar, salt, garlic powder, and pepper. Season as needed.
Pour the sauce over the potatoes and onions, cover with foil, and bake for 45 minutes.
Remove foil, sprinkle with Gruyre and Parmesan, and bake uncovered until golden brown and potatoes are tender. Let cool for 10 minutes and garnish with chives.
Store leftovers in an airtight container for up to 5 days and reheat in the microwave.
To make ahead, assemble the dish and refrigerate for up to 1 day before baking, adding extra baking time as needed.
Notes
For evenly cooked potatoes, try to slice them to a consistent thickness. A mandoline makes this incredibly easy.
Don’t skip the foil! Covering the dish initially helps the potatoes cook evenly without the top browning too quickly.
Letting the potatoes rest before serving allows the sauce to thicken slightly and the flavors to meld.
- Prep Time: 20 minutes
- Cook Time: 75 minutes
- Category: Side Dish
- Cuisine: American