Description
This classic Potatoes Au Gratin recipe features tender Yukon Gold potatoes baked in a creamy, cheesy sauce made with sautéed onions, garlic, and a blend of white cheddar and Parmesan cheeses. Perfectly layered and baked to golden perfection, this comforting casserole is a crowd-pleaser that pairs well with a variety of main dishes.
Ingredients
Scale
For the Sauce and Vegetables
- 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
For the Casserole
- 3 pounds Yukon Gold potatoes, sliced into â…›-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 your oven to 350°F (175°C). Lightly grease a 9×13 inch casserole dish with cooking spray to prevent sticking.
- Sauté Vegetables: In a skillet over medium-low heat, melt the butter. Add the chopped onion and minced garlic, cooking until the onion softens and becomes translucent. Sprinkle the flour over the mixture, stirring constantly and cooking for 2 more minutes to create a roux.
- Make Sauce: Gradually whisk in the chicken broth and milk until the sauce is smooth. Bring the mixture to a boil over medium heat while whisking constantly to prevent lumps. Season the sauce with salt and black pepper to taste.
- Layer Ingredients: In the prepared casserole dish, arrange one-third of the potato slices in an even layer. Pour one-third of the sauce over the potatoes, then sprinkle with ½ cup of the white cheddar cheese. Repeat these layers two more times, finishing with a topping of Parmesan cheese.
- Bake: Cover the casserole dish with aluminum foil and bake in the preheated oven for 45 minutes. Remove the foil and bake uncovered for an additional 45 minutes or until the potatoes are tender and the top is golden brown. For extra browning, you may broil the top for a few minutes, watching carefully to avoid burning.
- Serve: Garnish the finished potatoes au gratin with freshly chopped thyme. Serve hot and enjoy this comforting and cheesy potato dish.
Notes
- For thinner, creamier layers, slice potatoes as evenly as possible to about â…› inch thick.
- Using low-sodium broth helps control the saltiness; adjust seasoning before baking as needed.
- Broiling at the end should be done carefully to avoid burning the cheese.
- This dish can be prepared a day ahead and refrigerated; reheat covered in the oven.
- Substitute half and half for milk for a richer sauce if preferred.
