Potatoes Au Gratin

With a homemade cream sauce, and layers of parmesan and cheddar cheese, these potatoes au gratin are so rich and creamy!

Potatoes are a staple when it comes to side dishes, and this potatoes au gratin recipe proves it! They are perfect with most main dishes, just like our Oven Roasted Red Potatoes, Crock Pot Scalloped Potatoes, and Funeral Potatoes.

homemade Potato Casserole

I love a good side dish. Especially when the holidays roll around, I am all about the tasty sides! I love loading my plate with all the goods – from Mashed Potatoes to Stuffing, to Sweet Potato Casserole.

This delicious potato au gratin recipe is perfect for your holiday table (or for any other time you need a tasty side!) It’s easy to make, and incredibly cheesy and delicious!

The phrase “Au Gratin” makes these potatoes sound like super fancy gourmet potatoes, doesn’t it? Although it sounds fancy (and tastes like a million bucks in my opinion), this recipe is actually quite simple!

“Au Gratin” is French, and it literally means “by grating”. So you’ll see “au gratin” recipes topped with either bread crumbs, shredded cheese, or both – and then browned.

Au gratin or scalloped potatoes. Americans typically use the term interchangeably for sliced potatoes baked in a creamy sauce. If you want to get technical, au gratin potatoes have cheese, whereas scalloped potatoes traditionally don’t.

How to Make Au Gratin Potatoes

Au gratin potatoes are a creamy crowd-pleasing side dish with a quick prep.

POTATOES. Start by slicing your potatoes thinly (use a mandolin or chef’s knife). Spread them in a baking dish. I like to do the whole process in layers so I can maximize the amount of cheesy goodness.

PREP. Preheat the oven to 350°F. Spray a 9 x 9 casserole dish with cooking spray and set aside.

CHEESE SAUCE. In a medium saucepan, melt the butter. Whisk in the flour, and cook for 3-4 minutes, until golden brown. Slowly add the milk and cream, whisking constantly to prevent lumps. Cook an additional 5-6 minutes, or until thickened. Remove from heat. Stir in the salt, pepper, and one cup of the cheddar cheese.

LAYER Layer ⅓ of the potato slices, as evenly as possible, in the prepared baking dish. Pour ⅓ of the sauce over the potatoes, and spread to cover. Sprinkle ⅓ of the parmesan cheese and ⅓ of the remaining cheddar cheese over the top. Repeat the layers twice more.

BAKE. Cover with foil, and bake for one hour. Remove foil and bake for an additional 20-30 minutes, or until golden brown, and bubbling on top. Let cool for 15-20 minutes before serving.

It’s a good idea to let them sit before serving because the sauce will thicken up a little bit, so also account for 10-15 minutes of cool time after they come out of the oven.

Crockpot version

This potatoes au gratin recipe can easily be made in a slow cooker.

LAYER + COOK. Layer the potatoes, sauce, and cheese in the crockpot. Cook on high for 3-4 hours, or on the low setting for 6-8 hours.

This may yield a slightly different texture. It won’t have a crunch on the top as it would get from being in the oven, but the taste will be the same.

These au gratin potatoes are unbelievably delicious! They’re a little too rich to eat on a daily basis, but they’re perfect for a holiday or special dinner. They’re so tasty that you’ll be craving them constantly. 🙂

Recipe Tips

Homemade au gratin potatoes look like an extremely fancy dish, but are actually quite easy to assemble!

Potatoes. I used red potatoes for this dish. They are waxier and keep their shape really well. You also don’t need to peel them. My next choice would be Yukon Gold potatoes followed by russet potatoes. If you use russets, be sure to peel them first. 

Purple-colored potato slices are not harmful to eat, it simply looks a little off. The reason potatoes take on a purple hue is due to being exposed to air for a long period of time.

If you have sliced your potatoes in advance, simply put them in a bowl of cold water, and keep them in the fridge. This will keep them from coloring. Drain and pat dry before finishing the recipe. 

Flavor. These cheesy potatoes only need some salt and pepper, but if you wish to add extra flavor:

• Add onions, garlic, thyme, rosemary, parsley, or even nutmeg.
• Top with scallion for more flavor.
• Use gruyere cheese, jack cheese, or even asiago cheese. For best results, shred your own cheese as it melts better than pre-shredded packaged cheese.
• Add cooked protein such as cubes of baked ham, shredded chicken, or bacon bits to make this delicious side dish into a main meal. 

Doneness. When you think the dish is done, test a couple of different areas by stabbing the potato with a fork. If the potatoes are tender, and it slides through without resistance, the dish is done.

If the top is browning, but still needs more time to bake, tent a piece of tin foil over the dish to keep it from burning. 

Storing info

Make it ahead of time. Assemble this dish the day before. Be sure to cover it with plastic wrap, pressing the top of the casserole. Store in the fridge and bake according to directions.

STORE leftover easy au gratin potatoes in an airtight container in the fridge for 2-3 days.

Bake and freeze. Whether you are making them ahead of time, or have leftovers, allow the baked potatoes to cool before wrapping them tightly with plastic wrap and again with aluminum foil. Freeze for up to 1 month. Keep in mind the texture of potatoes does change when frozen.

Smaller portions are easy to reheat in the microwave, whereas larger portions should be reheated in the oven. Thaw in the fridge overnight. Set the oven to 325°F and heat for about 25-30 minutes until warm throughout. 

Recipe FAQ

For Even More Potato Side Dishes, Try:

• Twice Baked Potatoes
• Funeral Potatoes
• Brown Sugar Glazed Red Potatoes
• Cheesy Hasselback Potatoes
• Baked Mashed Potatoes
• Garlic Mashed Red Potatoes

I love potato dishes & these look amazing! Thank you Alicia for sharing! For more delicious recipes from Alicia, check out, The Baker Upstairs.

ENJOY!!