Layers of thinly sliced potatoes, onions and a delicious cheesy cream sauce make these Potatoes Au Gratin a hit side dish that’s perfect for the holidays or just because! This recipe is a family favorite and comes together easily, yet is incredibly delicious.
If you’re craving a comforting delicious side dish you can’t go wrong with potatoes au gratin! This is a side dish that has a fancy name, but it really easy to make.
Sliced potatoes and onions baked in a rich and creamy cheese sauce combine to make is the best side for holiday dinners or anytime you want to treat yourself to a decadent dish! It’s so cozy and so good!
You Will Love this Easy Recipe
- Despite the fancy name, this is a straightforward side dish recipe to make. There’s nothing complicated, and the ingredients are simple. I bet you have some of them on hand already!
- I’m sharing all of my tips for the best type of potato to use, how to slice them, and how to make the creamiest cheese sauce.
- If you’ve ever made baked macaroni and cheese, you can make this potato side dish!
The whole family is going to love this dish when you make it! My family does and I always print a few copies of the recipe because people always ask for it.
Best Potatoes for this Dish
I like to use yellow potatoes which are also called Yukon Golds. They have a great texture that’s a little waxy so the slices hold their shape with a buttery flavor. Plus, you don’t need to peel them.
You can use other kinds for this recipe, too.
- Russet potatoes work well, but I recommend peeling them because the skin is thick.
- You can also use red potatoes. They don’t need to be peeled, and the red skin will give the dish a little color.
The Creamy, Cheesy Sauce
The potatoes are layered with sliced onions and then baked in a creamy cheese sauce made with butter, flour, seasonings, heavy cream, cheese.
For the cheese, I recommend using sharp cheddar cheese but you can use other types of cheddar if you prefer. You can also use Gruyere cheese which will add a rich nutty flavor.
For the creamiest sauce be sure to use heavy cream. You can use half and half or whole milk but the sauce won’t be as rich and creamy.
How to Make It
Slice the potatoes very thin. The easiest way to do this is with a mandolin or you can use a sharp knife. The mandolin makes it easy to slice them so they are all of even thickness.
Slice the onions, too, and then layer the vegeables in the baking dish. I like to do several layers alternating the potatoes and onions.
Melt the butter in a saucepan over medium-high heat and then whisk in the flour. Whisk the mixture for a minute or so to cook off the raw flour taste.
Add all of the seasoning and whisk to combine. Slowly add the heavy cream and stir. Cook the sauce, stirring frequently, until it’s thickened.
Add the cheese and stir until it’s melted and the sauce is smooth. Pour the sauce over the vegetables in the baking dish.
Cover the baking dish with foil and bake it for 50 minutes.
Uncover the pan and bake for 10 minutes longer or until the sauce is bubbling around the edges.
Garnish with the parsley and serve warm from the oven.
Slicing Tip: The thickness of the sliced potatoes matters. If they are sliced thicker they will take longer to bake. Also, if they are sliced unevenly they may not bake evenly. This is why I use a mandolin, it makes it so much easier to evenly them.
Layering Tip: The easiest way to layer the potatoes and onions is to layer the potato slices flat with the onions on top. The tradeoff is that you won’t get crispy potatoes on top of the dish once it’s baked but it’s still really delicious.
For a fancier presentation, you can line the sliced potatoes up like books on a bookshelf with onion slices in between. This will take much longer but the tops of the potatoes will get crispier when baked.
Garnish Tips: Feel free to add a little more shredded cheese on top before you bake it or sprinkle some buttered breadcrumbs over the top for a crispy top. You can also garnish with fresh chopped chives instead of parsley.
They are very similar. Both have thin-sliced potato baked in a sauce, but traditional scalloped potatoes are usually made with a cream sauce while potatoes au gratin are made with a cheese sauce.
Lots of main dishes pair well with this dish! For holidays, it goes great with turkey or baked ham. For a special comfort food dinner, try it with homemade meatloaf, baked chicken thighs, or Parmesan pork chops!
Keep them in an airtight container in the refrigerator and they will store well for up to four days. Keep in mind that it won’t be as creamy when you reheat it because the sauce will thicken when chilled.
You can freeze the leftovers for up to two weeks. Thaw in the refrigerator before rewarming.
For the best creamy cheese sauce, I think it’s best to make this dish and serve it straight from the oven. For this reason, I don’t recommend making it ahead.
If you’ve been looking for a new easy side dish to try, you can’t go wrong with potato au gratin! It looks like a complicated dish but it’s so easy to make. It’s definitely a go-to when you want a creamy, cheesy, hearty side dish.
More Potato Side Dishes
- Hasselback Potatoes are baked potatoes thinly sliced like an accordion and stuffed with cheese, bacon, and other toppings. They are crispy and golden on the outside, soft and creamy on the inside!
- Garlic Parmesan Mashed Potato Casserole is a serious upgrade from plain mashed potatoes! It’s a great side dish for any holiday meal.
- Cottage Potatoes are always a family favorite! Cheesy, comforting, and great for potlucks and holidays.
Love this recipe? Be sure and comment below and leave a 5-star rating! I know you’ll love this delicious recipe as much as we do!
You can find more deliciousness on Instagram @julieseatsandtreats or #julieseatsandtreats, and be sure to tag your pics so I can see your yummy dish!!
- 3 pounds yellow potatoes thinly sliced (about 12-14 potatoes)
- 1 yellow onion thinly sliced
- 3 ½ Tbsp unsalted butter
- 3 ½ Tbsp all-purpose flour
- 1 tsp salt
- 1 tsp garlic powder
- ½ tsp onion powder
- ½ tsp dried basil
- ¼ tsp dried rosemary
- ¼ tsp pepper
- 2 c. heavy cream
- 1 ¼ c. sharp cheddar cheese
- Parsley chopped (optional garnish)
- Preheat the oven to 400 degrees Fahrenheit. Prepare a 9X13 baking dish by spraying it with cooking spray.
- Place one layer of sliced potatoes on the bottom of the baking dish. Sprinkle on ¼ of the sliced onions on top of the potato layer. Repeat with the potatoes and onions until you have used all of the potatoes and onions. Set aside.
- In a medium saucepan over medium high heat, melt the unsalted butter and whisk in the flour. Continue to whisk for one to two minutes.
- Add in the garlic powder, onion powder, dried basil, dried rosemary, and pepper. Whisk together.
- Slowly whisk in the heavy cream and cook until thickened, stirring frequently.
- Dump all the cheese into the saucepan and mix until the cheese is completely combined.
- Pour the cheese sauce over the potatoes and onions in the baking dish.
- Cover the pan with aluminum foil and bake in the oven for 50 minutes.
- Take off foil and return pan to oven for an additional 10 minutes or until the top is set and the sides are bubbly.
- Garnish with chopped parsley (optional) and then plate and serve. Best when served warm.