Description
This classic Potatoes Au Gratin recipe features tender slices of Yukon Gold potatoes layered with a creamy cheese sauce made from butter, onions, garlic, flour, chicken broth, and whole milk. Baked until golden and bubbling, the dish is finished with Parmesan cheese and fresh thyme for a rich, flavorful side that pairs perfectly with any meal.
Ingredients
Scale
Cheese Sauce
- ¼ cup unsalted butter
- 1 medium onion, chopped
- 3 cloves garlic, minced
- ¼ cup all-purpose flour
- 1 cup low-sodium or no-sodium chicken broth
- 2 cups whole milk (or half and half)
- ½ teaspoon salt, or to taste
- ½ teaspoon black pepper, or to taste
Main Ingredients
- 3 pounds Yukon Gold potatoes, sliced into ⅛-inch rounds
- 2 cups freshly grated white cheddar cheese
- ½ cup freshly grated Parmesan cheese
- 1 tablespoon fresh thyme, chopped, for garnish
Instructions
- Preheat and Prep: Preheat the oven to 350°F (175°C). Lightly grease a 9×13 inch casserole dish with cooking spray to prevent sticking during baking.
- Sauté Vegetables: Melt the butter in a skillet over medium-low heat. Add the chopped onion and minced garlic, cooking them until softened and fragrant. Sprinkle the flour over the mixture and continue to cook for 2 more minutes while stirring constantly to make a roux and remove raw flour taste.
- Make Sauce: Gradually whisk in the low-sodium chicken broth and whole milk until the mixture is smooth. Increase heat to medium and bring the sauce to a boil, whisking constantly to thicken. Season the sauce with salt and black pepper to taste.
- Layer Ingredients: In the prepared casserole dish, arrange one-third of the sliced potatoes in an even layer. Pour one-third of the sauce over the potatoes, then sprinkle ½ cup of grated cheddar cheese evenly on top. Repeat this layering process two more times, finishing with the Parmesan cheese sprinkled on the top layer.
- Bake: Cover the casserole dish tightly with aluminum foil and bake for 45 minutes. Then uncover and bake for an additional 45 minutes or until the potatoes are tender and the top is golden brown. If you desire more browning, broil the dish for a few minutes, watching carefully to avoid burning.
- Serve: Remove from the oven and let it rest for a few minutes. Garnish with chopped fresh thyme and serve hot as a delicious side dish.
Notes
- Use Yukon Gold potatoes for their creamy texture and smooth melting properties.
- Slicing the potatoes thinly (⅛ inch) ensures even cooking and a tender final dish.
- Adjust salt and pepper in the sauce according to your taste preference.
- Covering the dish during the first baking phase helps the potatoes cook evenly and retain moisture.
- Broiling at the end adds a gorgeous golden crust but watch carefully to prevent burning.
- This dish can be prepared a day ahead and reheated before serving.
