Name: Au Gratin Potatoes
Prep time: 20 min
Cook time: 1 h 10 min
Total time: 1 h 45 min
Cuisine: American
Ingredients: 2 ½ lb Russet potatoes, peeled and sliced ⅛ inch thick; 2 tbsp butter; 2 tbsp all-purpose flour; 1 cup whole milk (room temperature); 1 cup heavy cream; 2 garlic cloves, minced or pressed; 1 ½ cups sharp cheddar cheese, freshly shredded; ½ cup Gruyère or Parmesan (optional, for deeper flavor); Salt and pepper, to taste

Why You’ll Love This Recipe

I love how this dish transforms humble potatoes into something elegant and indulgent. The combination of sharp cheddar, a hint of Gruyère or Parmesan, and a velvety sauce gives every bite incredible depth. It’s also a make-ahead dream—perfect for prepping earlier in the day and baking just before guests arrive. The crispy golden top and creamy center always win everyone over.

Ingredients

(Here’s a tip: Check out the full list of ingredients and measurements in the recipe card below.)

2 ½ lb Russet potatoes – peeled and sliced ⅛ inch thick
2 tablespoon butter
2 tablespoon all-purpose flour
1 cup whole milk – room temperature
1 cup heavy cream
2 garlic cloves – minced or pressed
1 ½ cup sharp cheddar cheese – freshly shredded
½ cup Gruyère or Parmesan (optional, for deeper flavor)
Salt & pepper – to taste

Directions

I start by peeling and slicing the potatoes very thin—about ⅛ inch thick. Using a mandoline makes this easy and keeps the slices uniform. I rinse the slices under cold water to reduce excess starch.
In a saucepan, I melt the butter over medium heat, add the garlic, and cook for about 30 seconds. Then I whisk in the flour to make a roux.
Gradually, I add the milk and cream, whisking constantly until the sauce is smooth and starts to thicken.
Once the sauce is velvety, I stir in the cheddar cheese (and Gruyère or Parmesan if I’m using it), then season with salt and pepper to taste.
In a greased 9×13 baking dish, I layer the potato slices and pour a bit of the cheese sauce over each layer, repeating until everything is used up. I top it all with a final layer of cheese.
I cover the dish with foil and bake in a preheated oven at 375°F (190°C) for about 60–70 minutes, removing the foil during the last 15 minutes to let the top get golden and bubbly.
After baking, I let the dish rest for 10–15 minutes before serving so the sauce can set and the flavors can meld.

Servings and timing

This recipe serves 6 and takes about 1 hour and 45 minutes from start to finish:

Prep Time: 20 minutes
Cook Time: 1 hour 10 minutes
Resting Time: 15 minutes
Total Time: 1 hour 45 minutes

Variations

When I want to change things up, I swap in Yukon Gold potatoes for a creamier texture or add caramelized onions between the layers for a sweet, savory twist. Sometimes I mix in smoked paprika or fresh thyme to the sauce for extra flavor. For a more rustic version, I leave the potato skins on. And if I want to add protein, thin slices of ham or crumbled bacon work beautifully layered in.

Storage/Reheating

Leftovers keep well in the fridge for up to 3 days in an airtight container. To reheat, I cover the dish with foil and warm it in the oven at 350°F until heated through. The microwave works for single servings, but I make sure to reheat slowly so the sauce stays creamy.

FAQs

Can I make these potatoes ahead of time?

Yes, I often assemble the dish a few hours in advance, then cover and refrigerate it. When I’m ready to bake, I let it sit at room temperature for about 20 minutes before putting it in the oven.

What’s the best cheese to use?

Sharp cheddar is my go-to for its bold flavor, but I love adding a bit of Gruyère or Parmesan for a more complex taste.

Do I have to peel the potatoes?

No, if I’m short on time or want a rustic feel, I leave the skins on. Just be sure to scrub them well.

Can I freeze au gratin potatoes?

I don’t recommend freezing before baking, as the sauce can separate. But once baked and cooled, they freeze well. I wrap portions tightly and reheat in the oven.

How do I prevent the sauce from curdling?

I make sure to use room-temperature milk and cream and warm the sauce gently without boiling. This keeps it smooth and prevents separation.

Conclusion

Au Gratin Potatoes are one of those timeless side dishes that never goes out of style. I love how they elevate any meal with their rich, cheesy layers and tender texture. Whether I’m cooking for a crowd or just treating myself, this dish always delivers that warm, satisfying bite I crave.