I love this recipe because it turns simple ingredients into something elegant and deeply satisfying. The creamy sauce infused with garlic and onion complements the tender potatoes perfectly. The blend of cheddar and Gruyère gives the dish a rich, nutty flavor and a beautiful crust when baked. It’s an easy, make-ahead classic that always impresses family and guests alike.
Ingredients
(Note: All ingredient amounts are listed in the recipe card below.)
6 medium Russet potatoes 6 tablespoons butter 6 tablespoons all-purpose flour 2 cups milk 1 cup heavy whipping cream 1 teaspoon salt 2 cloves garlic, minced 1½ teaspoons dried onion flakes Salt and freshly ground black pepper, to taste 3 cups freshly grated sharp cheddar cheese or Gruyère (or a mix of both)
Directions
I start by making the cheese sauce. In a medium saucepan over medium heat, I melt the butter and whisk in the flour, cooking for about 1–2 minutes until smooth and lightly golden. Then I slowly pour in the milk and cream while whisking continuously to avoid lumps. I stir in the minced garlic, dried onion flakes, salt, and pepper, and let the mixture simmer on low heat until it thickens slightly. Next, I reduce the heat and stir in 2 cups of the shredded cheese until melted and smooth. I taste and adjust the seasoning to my liking. For the potatoes, I peel them (though sometimes I leave the skin for a rustic touch) and slice them into thin, even slices about ⅛ inch thick. I use a mandoline slicer when I want perfectly even layers. I lightly grease a 9×13-inch casserole dish and spread half of the sliced potatoes evenly in the bottom. Then I pour half of the cheese sauce over them and spread it gently to coat. I add the remaining potato slices on top and pour over the rest of the cheese sauce, spreading it evenly. Finally, I sprinkle the remaining 1 cup of cheese across the top for that irresistible golden crust. I cover the dish with foil and bake it in a preheated oven at 350°F (175°C) for 30 minutes. Then I remove the foil and continue baking for another 30 minutes until the potatoes are tender and the top is golden and bubbly. Before serving, I let it rest for about 10 minutes so the sauce can thicken slightly.
Servings and Timing
This recipe serves 12 people. Prep Time: 20 minutes Cook Time: 1 hour Total Time: 1 hour 20 minutes
Variations
When I want a sharper taste, I use more Gruyère or even add a bit of Parmesan to the top. For a twist, I’ve added caramelized onions or thinly sliced leeks to the layers—they make the dish even more aromatic. I’ve also made a lighter version using half-and-half instead of cream and less butter, and it still tastes delicious.
Storage/Reheating
I store leftovers in an airtight container in the refrigerator for up to 3 days. To reheat, I cover the dish with foil and warm it in the oven at 350°F until heated through. If I’m in a hurry, I microwave individual portions, but I prefer the oven for keeping the top crispy. This dish also freezes well—once cooled, I wrap it tightly and freeze for up to 2 months.
FAQs
Can I slice the potatoes ahead of time?
Yes, but I keep them submerged in cold water to prevent browning and pat them dry before layering.
What’s the best cheese for Potatoes Au Gratin?
I love using a mix of sharp cheddar and Gruyère for the best balance of flavor and meltiness.
Can I make this dish vegetarian?
Yes, it already is as long as the cheese doesn’t contain animal rennet.
Can I use half-and-half instead of heavy cream?
Yes, it works well and makes the sauce slightly lighter.
How do I know when the gratin is done?
I check by piercing the potatoes with a knife—they should be tender and the top golden and bubbly.
Why did my sauce turn grainy?
That can happen if the cheese was added over high heat. I always lower the heat before stirring in the cheese.
Can I make this ahead of time?
Yes, I assemble it up to a day ahead, cover it tightly, and refrigerate it. Then I bake it just before serving.
What potatoes work best?
Russet potatoes are great because they’re starchy and create a creamy texture, but Yukon Golds also work beautifully.
Can I freeze Potatoes Au Gratin?
Yes, I let it cool completely, wrap it well, and freeze it for up to 2 months. I thaw it overnight before reheating.
Conclusion
I love how Potatoes Au Gratin takes simple ingredients and transforms them into something irresistibly rich and comforting. The creamy layers, melted cheese, and tender potatoes make it the perfect side for any meal or a satisfying dish all on its own. Every bite feels like pure comfort, and it’s a recipe I find myself coming back to time and time again.
A rich, creamy, and comforting classic, Potatoes Au Gratin features thinly sliced potatoes baked in a luscious cheese sauce made with cheddar and Gruyère. Golden and bubbly on top with tender layers beneath, this dish is a perfect side for any meal or a cozy main course.
Ingredients
6 medium Russet potatoes
6 tbsp butter
6 tbsp all-purpose flour
2 cups milk
1 cup heavy whipping cream
1 tsp salt
2 cloves garlic, minced
1½ tsp dried onion flakes
Salt and freshly ground black pepper, to taste
3 cups freshly grated sharp cheddar cheese or Gruyère (or a mix of both)
Instructions
Preheat oven to 350°F (175°C) and lightly grease a 9×13-inch casserole dish.
In a medium saucepan, melt butter over medium heat. Whisk in flour and cook for 1–2 minutes until smooth and lightly golden.
Gradually pour in milk and cream while whisking constantly to avoid lumps. Stir in minced garlic, dried onion flakes, salt, and pepper. Simmer on low heat until slightly thickened.
Reduce heat and stir in 2 cups of shredded cheese until melted and smooth. Adjust seasoning to taste.
Peel and thinly slice the potatoes (about ⅛ inch thick). Layer half the potato slices evenly in the prepared baking dish.
Pour half of the cheese sauce over the potatoes and spread evenly. Add the remaining potato slices on top and pour over the rest of the sauce.
Sprinkle the remaining 1 cup of cheese evenly across the top.
Cover with foil and bake for 30 minutes. Remove the foil and bake for another 30 minutes, or until the potatoes are tender and the top is golden and bubbly.
Let the gratin rest for 10 minutes before serving to allow the sauce to thicken.
Notes
Use a mix of cheddar and Gruyère for the best flavor and texture.
For extra flavor, add caramelized onions, leeks, or a sprinkle of Parmesan on top.
Make it ahead of time and bake before serving.
Reheat covered with foil in the oven to keep the top crispy.
Freeze cooled gratin for up to 2 months for easy make-ahead meals.
