Ultimate Cheesy Béchamel Potatoes Au Gratin

Q: What are Potatoes au Gratin?

This is a French potato side dish casserole consisting of thinly sliced potatoes, layered with a white sauce and topped with cheese and breadcrumbs, then baked in the oven. This is easy to make and you’ll want to make this for all of your holiday meals, or even if you just want to switch up the usual weeknight meal plan!

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About this recipe

Make the best au gratin potatoes from scratch with a rich, cheesy béchamel sauce and golden, crispy top. No cream needed — just pure comfort food perfection in every bite.

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Incredible Cheesy Potato Gratin Recipe

Easter is just around the corner, and in my opinion, a potato side dish really completes the meal! My love for potatoes has grown strong ever since I was a little boy!

Something that has always been on my bucket list was to make scalloped potatoes. Now, those are coming, but when I discovered Au Gratin Potatoes, I wanted to make those first! I mean, who can resist THE CHEESE?

I know I cannot, and that’s why I was so excited to prepare these super cheesy potatoes! These potatoes are actually super easy to make and require very little hands-on work! If you’ve always wanted to prepare these special potatoes, then this Easter will be perfect occasion to check this off your bucket list as part of your Live to Cook one-month challenge! Sign up to my free email newsletter to get started on your cooking journey today, plus you’ll always have dinner inspiration sent straight to your inbox!

Check out the video to follow along to see how to make the white sauce and how to assemble this incredible potato casserole! If you haven’t already, it would mean a lot if you would please subscribe to my YouTube channel, and be sure to press the bell icon so you’re notified when all of my video recipes are live! Let’s get cooking!

Golden-brown baked potato gratin in a white ceramic dish with melted cheese and crispy breadcrumb topping.

What are Potatoes au Gratin?▼

This is a French potato side dish casserole consisting of thinly sliced potatoes, layered with a white sauce and topped with cheese and breadcrumbs, then baked in the oven. This is easy to make and you’ll want to make this for all of your holiday meals, or even if you just want to switch up the usual weeknight meal plan!

Why YOu’ll Love This Cheesy Au Gratin Potatoes Recipe!

Easy to make: All you need to do is make the béchamel sauce then bake!
Cheesy: If you’re a cheese lover, then this is definitely the potato dish for you!
Great for a crowd: Depending on what size of casserole you use, you can feed lots of hungry mouths!
Make-ahead friendly: If you’ve got a lot of components going on for your holiday feast, then cheesy potato gratin is a great option because you can let it bake in the oven as you prepare more involved dishes, and you can even make this the night before the event that you are hosting!

What is the difference in scalloped and au gratin potatoes?▼

I have to admit that pretty much up until I actually made the dish I was very confused about the differences between Scalloped Potatoes and Au Gratin Potatoes. When you’re searching for one, you get results of the other, and it’s really hard to distinguish what is what. Once you know, you can really wrap your ahead around it! By the way, if you do want to make scalloped potatoes, then check out my recipe here!

The cheese sauce for the two dishes is béchamel sauce or cream sauce for both dishes, however, the key difference that sets au gratin potatoes apart from scalloped potatoes is the addition of cheese and breadcrumbs to the recipe. Au Gratin potatoes hail from the Dauphiné region of south-east France, not too far from Italy. The French name for this potato dish is actually Gratin Dauphinois. “Au gratin” literally means “with a crust,” and this refers to the cheese and breadcrumb crust that will be added to the potatoes before baking. “Au gratin” means refers to the method of adding a crust to a dish, so the dish translates to “potato with a crust! On the other hand, the origins of “scalloped” potatoes are less known, but it is believed that this dish originated in England, because scalloped potatoes, along with other “scalloped” recipes, originate from the original dish - baked oysters and breadcrumbs.

Furthermore, another the potato rounds of scalloped potatoes are cut into thicker pieces than au gratin potatoes. This is because we want thinner potato pieces for the au gratin potatoes to get a satisfying experience of biting through many layers, almost like a lasagna made with potatoes instead!

What are the best potatoes FOr Bechamel Potatoes Au Gratin?▼

You want to choose a starchy potato for this recipe. This is because you want the moisture in the potatoes to evaporate, and this helps to cook the potatoes. These can be Yukon gold potatoes or Russet potatoes. For my recipe, I’m going to use Yukon gold potatoes.

Creamy potato au gratin with golden cheese topping being served with a spoon from a white dish.

What cheese should I use?▼

For these bechamel potatoes, using a combination of cheddar cheese and Gruyère cheese. In particular, the cheddar cheese I’m using is Red Fox aged cheese, which is quite strong! Gruyère is the ideal choice because of its flavour and because it’s an excellent cheese for melting. Lots of recipes top their casseroles with Parmesan as well, but since Gruyère cheese is very strong on its own, I didn’t think that Parmesan cheese was needed this time. Use this time to experiment with similar cheese combinations for your dish.

What If I don’t have a Mandolin slicer?▼

Well technically a mandolin in this case would be considered a luxury, it’s satisfying to get clean even cuts rather quickly using a mandolin. But I’d argue its just fine to use your hands and a knife and get very similar results. Make conscious, deliberate cuts to the potatoes to get 1/8th inch thick slices.

Baked potato gratin with golden-brown cheese topping and creamy béchamel sauce in white bowl

Why Did My Potatoes Curdle?▼

The milk or béchamel sauce can curdle for a couple of reasons, but in essence when the proteins in the milk denature, it causes the split. This can occur for several reasons, some of them being cooking the casserole at high temperatures and for cooking for extended durations.

Make sure to cook out the roux for the béchamel really well before adding the milk and then mixing the ingredients well together.
Sometimes older milk can curdle much easier than fresh milk, so try and use the freshest sourced milk if possible.
Try to keep the temperature range between 350 to 375 F.

Tools Needed

Ingredients for the Best Potato Gratin Recipe

The FULL PRINTABLE RECIPE CARD can be found by scrolling to the bottom of this post or by pressing the “Jump to Recipe” button. You will also be able scale the recipe based on how large your casserole is or how many people you’re looking to feed - you’ll know exactly how many potatoes and cheese you’ll need for everyone to get a wholesome portion!

Ingredients for potato gratin arranged on a dark surface: Yukon gold potatoes, shallots, butter, garlic, cream, cheese, and fresh thyme.

Potatoes: My favourite type of potato for nearly everything is Yukon gold potatoes. You get a buttery and creamy flavor, plus Yukon gold potatoes are excellent in holding their shape.
Herbs: A sprig of fresh thyme.
Milk: I used whole milk here, and this will give you the best results. You add the milk to the flour and butter, which is the roux. Cold milk is optimal to prevent lumps in your sauce!
Butter: Unsalted butter is my recommendation so that you have better control over the amount of salt.
All-purpose flour: You mix this with butter to make the roux.
Shallots: I will first sauté the shallots with the roux before adding the milk. This will give an excellent aroma.
Garlic cloves: Sauté these with the shallots. Discard afterward.
Seasonings: Freshly ground nutmeg and dried sage leaves. For the nutmeg, I grated whole nutmeg, but you can use pre-ground nutmeg if you want.
Cheeses: I used a combination of cheddar cheese and Gruyère cheese.
Breadcrumbs: Plain breadcrumbs for topping. You could use Panko breadcrumbs if you really want to, but it doesn’t matter so much which kind of breadcrumbs you use for this recipe.

How to Make Cheesy Au Gratin Potatoes

Preheat the oven to 350F. Peel the potatoes and slice to 1/8th inch thick slices.

Hand holding a peeled potato over a cutting board with potato slices nearby.

Hand holding a peeled potato next to a ruler measuring its thickness for slicing.

Slicing peeled potatoes into thin rounds on a wooden cutting board for au gratin preparation.

Hands slicing peeled potatoes into thin rounds on a wooden cutting board with a knife.

Add the potatoes to a large bowl and set aside for now.

Thinly sliced potatoes in a glass bowl filled with water, prepared for cooking.

Heat a pan on medium heat and add butter. Once the butter melts, add in the shallots and sauté for 5-6 minutes. Mix in the flour and whisk for 2-3 mins until the rawness of the flour is cooked out. The roux will begin to smell nutty, which is a good indicator that it is cooked.

Milk being whisked into a roux in a stainless steel saucepan to make béchamel sauce for potatoes au gratin.

Butter melting in a saucepan with milk being added while whisking to make béchamel sauce for potatoes au gratin.

Milk being poured into a saucepan with shallots and roux for béchamel sauce, whisking to combine.

Whisking milk into a roux with shallots in a saucepan to make béchamel sauce for potatoes au gratin.

Béchamel sauce simmering in a saucepan with shallots and herbs on stovetop.

Whisking milk into a roux-based sauce in a saucepan on the stovetop for béchamel preparation.

Butter and shallot roux being whisked in a saucepan during béchamel sauce preparation.

Creamy béchamel sauce simmering in a stainless steel pan on an induction cooktop.

Pour in your milk, little bit at a time while whisking to work out any lumps. Once all your milk is mixed in, wait until your sauce starts to come up to a simmer.

Pouring milk into a pan with a roux-based sauce while whisking to make béchamel.

Whisking creamy béchamel sauce in a saucepan on the stovetop.

Whisking creamy béchamel sauce in a saucepan on the stovetop during preparation.

As soon as the sauce comes to a simmer, it will begin to thicken. Add the thyme, sage and garlic cloves, salt and pepper. Once the béchamel is thick enough to evenly coat the back of a spoon, season with nutmeg, salt and pepper.

Creamy béchamel sauce simmering in a saucepan with paprika sprinkled on top, being stirred with a whisk.

Garlic cloves on a wooden cutting board next to a bowl of béchamel sauce.

Creamy béchamel sauce simmering in a pot with diced vegetables and red paprika garnish on the stovetop.

Red shaker sprinkling herbs and spices into a pot of simmering béchamel sauce on a stovetop

Hand whisking creamy béchamel sauce with herbs in a saucepan on stovetop.

Creamy béchamel sauce simmering in a pot with a spatula, showing thickened consistency with herbs and seasonings mixed in.

Add the béchamel to the potatoes and mix well.

Creamy béchamel sauce being poured over sliced potatoes in a glass bowl for mixing.

Creamy béchamel sauce with butter and herbs being stirred into sliced potatoes in a glass bowl.

Spray a casserole dish with oil or brush with melted butter. My casserole is roughly 9 x 6 inches. Add the potatoes and béchamel to the casserole and spread and pat down to make it even.

Brushing melted butter onto a white oval casserole dish with a blue pastry brush.

Sliced potatoes mixed with creamy béchamel sauce in a white oval casserole dish, ready to bake.

Cover tightly with aluminum foil and bake for 50-60 minutes or until the potatoes are fork tender. Top with the cheeses, sprinkle breadcrumbs and bake for 20-30 more minutes or until the cheese has browned and formed a crust.

Hands removing aluminum foil from a baked potato gratin casserole dish.

Hand pouring melted butter over cheesy béchamel potatoes au gratin in a ceramic baking dish.

Baked potatoes au gratin in a white oval dish topped with melted cheddar cheese and breadcrumbs on a dark surface.

Let the casserole rest for at least 15 minutes before serving.

Baked potato au gratin in a white ceramic dish with golden breadcrumb topping and melted cheese.

Enjoy!

A fork lifting a bite of golden, creamy cheesy potato gratin from a white plate, showing its layered texture.

TIPS to Have Delightful Au Gratin Potatoes

Slice the potatoes evenly to ensure they cook at the same rate and consistency.
Cook the roux for the béchamel until it darkens slightly and smells nutty.
Discard the thyme and cloves of garlic before baking the casserole. We only need these to scent the sauce.
Make sure the casserole is tightly covered to allow the steam cook the potatoes low and slow.
In case the sauce splits or curdles, add some heavy cream, lightly mix together and continue baking.

Variations

Meat: This recipe is vegetarian so that it’s accessible to all. However, if you’re serving this for meat lovers, then perhaps add some ham, bacon or sausage!
Cheese: Gruyère is key for the right flavour you want in a classic au gratin potatoes. However, it is really expensive! I would honestly recommend you invest your gruyere for this, plus you’ll have lots left over so you can use it in other recipes, such as
Herbs: You could garnish with parsley, dill or chives instead of thyme.
Sauce: Since we’ve got lots of cheese to make these potatoes really rich, I’m just using a standard béchamel sauce with milk. However, if you want to make the sauce richer, feel free to add some heavy cream too! Actually, some cream could prevent the béchamel sauce from splitting, as discussed previously.

Baked potato gratin in a white dish with golden-brown cheese crust and creamy layers visible from the side.

Serving Suggestions

You can serve these potatoes as part of a complete holiday meal! Here are just a couple of ideas to help you craft the perfect meal for your family and friends!

Creamy cheesy potatoes au gratin in a white baking dish with golden-brown top and melted cheese.

Can I Make Au Gratin Potatoes ahead of time?▼

Yes, you can! This dish make for an amazing side dish for holiday meals not only because they require little hands-on work, but they’re great to make in advance and to leave in the fridge!

Storage Instructions

You can keep your potatoes in the casserole and place the casserole directly in the fridge, provided there’s space for it! If your casserole doesn’t have a lid, cover the top with plastic wrap. You can keep it in the fridge for 3 to 4 days because of the dairy in here. I wouldn’t freeze the potatoes because I don’t like the texture of potatoes when they have been frozen and thawed - I just don’t think you’ll get the same crispiness as you get in the fresh version!

How to Reheat▼

I wouldn’t recommend that you reheat your potatoes in the microwave because you’ll lose the shape of the potatoes and as a result, lose the layers! Although it will take some time, I definitely suggest that you reheat your Au Gratin Potatoes in the oven! Preheat the oven to 350F and reheat for about 25 to 30 minutes, depending on how much you’ll be reheating.

In the mood for something simpler? Make an easy jacket potato.

Let me know what you think of this recipe in the comments! If you’ve tried this recipe, be sure to post it on social media and tag it with #cookingwithanadi and mention me @cooking.with.anadi. Thank you!

Recipe by Anadi Misra