This Creamy Au Gratin Potatoes recipe is an indulgent, cheesy side dish featuring layers of tender Yukon gold potatoes baked in a rich, savory sauce. The combination of Fontina, Gruyère, and Parmigiano cheeses creates a perfectly creamy texture with a golden, crispy top. Whether served as a side dish or a comforting main course, this dish is packed with flavor and irresistible cheesy goodness.

Why You’ll Love This Recipe

Rich and creamy texture with perfectly tender potatoes
Three types of cheese for a deliciously complex flavor
Crispy golden top with a luscious, cheesy interior
Perfect for holidays or special occasions
Easy to make ahead and reheat

Ingredients

(Tip: You can find the complete list of ingredients and their measurements in the recipe card below.)

For the Au Gratin Potatoes:

6 medium Yukon gold potatoes, thinly sliced
1 medium onion, thinly sliced
3 tablespoons butter
3 tablespoons all-purpose flour
½ teaspoon salt
Salt and ground black pepper, to taste
2 cups whole milk
1 cup Fontina cheese, shredded
½ cup Gruyère cheese, shredded
½ cup Parmigiano cheese, grated
1 sprig fresh thyme

Directions

Step 1: Prepare the Ingredients

Preheat the oven to 375°F (190°C). Grease a 9×13-inch baking dish with butter or cooking spray.
Wash and peel the potatoes, then thinly slice them into uniform rounds. Thinly slice the onion.

Step 2: Make the Creamy Cheese Sauce

In a saucepan over medium heat, melt the butter. Add the sliced onions and cook until softened, about 3 minutes.
Stir in the flour and cook for another minute, whisking continuously.
Slowly pour in the whole milk, whisking to avoid lumps. Continue stirring until the mixture thickens.
Remove from heat and stir in Fontina and Gruyère cheeses until melted. Season with salt and black pepper.

Step 3: Assemble the Dish

Arrange half of the sliced potatoes in an even layer in the prepared baking dish.
Pour half of the cheese sauce over the potatoes.
Repeat with the remaining potatoes and cheese sauce.
Sprinkle the grated Parmigiano cheese on top and add a sprig of fresh thyme.

Step 4: Bake

Cover the dish with foil and bake for 45 minutes.
Remove the foil and bake for an additional 15–20 minutes, until the top is golden and crispy.
Let cool for 10 minutes before serving.

Servings and Timing

Servings: 6
Preparation Time: 15 minutes
Cooking Time: 1 hour
Total Time: 1 hour 15 minutes

Variations

Extra Garlic Flavor: Add 2 cloves of minced garlic to the butter when cooking the onions.
Spicy Kick: Add a pinch of cayenne pepper or red pepper flakes.
Bacon Lover’s Version: Sprinkle crispy bacon bits between the layers.
Herb Infusion: Replace thyme with rosemary or sage for a different aromatic touch.
Dairy-Free Alternative: Use plant-based butter, almond milk, and dairy-free cheese substitutes.

Storage/Reheating

Refrigeration: Store leftovers in an airtight container for up to 4 days.
Freezing: Freeze in a sealed container for up to 2 months. Thaw overnight in the refrigerator before reheating.
Reheating: Warm in a 350°F oven for 15–20 minutes or microwave in 30-second intervals until heated through.

FAQs

Can I use a different type of potato?

Yes, Russet potatoes work well, but Yukon gold potatoes provide the best creamy texture.

How do I get a crispy top?

Remove the foil in the last 15–20 minutes of baking and broil for 2–3 minutes if needed.

Can I make this dish ahead of time?

Yes, assemble it a day in advance, cover it, and refrigerate. Bake when ready to serve.

Can I use pre-shredded cheese?

Freshly shredded cheese is recommended for better melting and a creamier texture.

Is this recipe gluten-free?

Use gluten-free flour to make it suitable for gluten-free diets.

Can I add more cheese?

Absolutely! Extra cheese will make the dish even richer.

Why is my sauce too thick?

If the sauce thickens too much, add a splash of warm milk while stirring.

Can I add protein to make it a main dish?

Yes, shredded chicken or cooked ham make great additions.

Can I use half-and-half instead of whole milk?

Yes, but it will make the sauce even richer and creamier.

How do I prevent the potatoes from being undercooked?

Ensure the slices are uniform in thickness and bake long enough for them to become tender.

Conclusion

These Creamy Au Gratin Potatoes are a rich, indulgent dish perfect for any occasion. With layers of tender potatoes, a creamy cheese sauce, and a crispy golden topping, this dish is both comforting and elegant. Whether served as a side dish or a main course, this recipe is sure to be a crowd-pleaser. Try it today and enjoy every creamy, cheesy bite!