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Potatoes Au Gratin

A warm and cheesy side dish to serve with any meal.

This potatoes au gratin recipe is delicious, with tender sliced potatoes in a cheesy sauce and coated with breadcrumbs.

It’s a wonderful side dish to serve with ham over the holidays, roast beef, pork tenderloin or roasted chicken.

Potatoes au gratin with breadcrumbs in a white casserole dish with a serving taken out of the corner.

Tender Cheesy Potatoes

This is a wonderful way to change up your potato routine. The prep is quite simple and looks more complicated than it actually is.

  • This is a great side dish to prep in advance and heat up just before dinner.
  • A cheesy sauce is created with melted cheese, butter, milk and flour.
  • Au gratin means covered with breadcrumbs or cheese and browned. This is usually done under a broiler.
  • Thinly sliced potatoes are easy to prep by hand or with a mandoline slicer.
  • This recipe uses basic ingredients that are simple and affordable.
  • The cheesy sauce can easily be made gluten-free with an alternative flour and breadcrumbs.
Recipe ingredients on counter including potatoes, bowl of shredded cheese, flour, milk, butter, onion and breadcrumbs.

Recipe Ingredients

POTATOES: The perfect au gratin potatoes require six medium yellow or russet potatoes. The peel can be left on or taken off during prep.

SAUCE: Salted butter, flour, milk and shredded cheese are combined to create a cheesy sauce, which is what makes this recipe so delicious.

CHEESE: Shredded cheddar cheese is an excellent addition to the sauce. Some recipes use parmesan and gruyere, or swiss cheese for sharper flavors. I chose to keep things more simple (and affordable) by sticking with cheddar.

BREADCRUMBS: Sprinkled on top in the last 30 minutes of baking, this adds a nice texture and crunch to the meal. Some au gratin potato recipes omit the breadcrumbs, so this step is optional depending on preference. Personally, we love them added in.

Four images showing steps to make recipe: first is sliced thin potatoes on a cutting board with a knife. Second is sliced potatoes in a white casserole dish. Third is melted cheese sauce drizzled over potatoes in baking dish, fourth is added breadcrumbs and shredded cheese over recipe.

How To Make Au Gratin Potatoes

Potatoes au gratin is an easy recipe to master and wow your guests with.

  1. Slice potatoes and onion into thin strips, then spread into prepared casserole dish.
  2. Melt butter in a pot, and add flour according to the full recipe instructions below.
  3. Add milk, boil, then add in cheese.
  4. Drizzle sauce over potatoes. Cover and bake 1 hour. Remove foil, add breadcrumbs and bake 20 minutes until golden and crispy.
Au gratin potatoes in a baking dish.

Recipe Tips

  • Scrub the potatoes and slice off any bruises / bad spots. Then slice each potato thin, about ½ thick. There’s no need for a mandoline slicer, however these are definitely handy if you have one.
  • It’s okay to use potatoes with small sprouts. These can be snapped off with your fingers or sliced off with a knife.
  • Potatoes should be completely dry before assembling the recipe. Pat them with a paper towel. This will produce crispier potatoes.
  • Lightly grease the casserole dish with nonstick cooking spray before adding potatoes.
  • While prepping the cheese sauce, stir constantly to avoid any burning.
  • Feel free to add more grated cheese with breadcrumbs to make it extra cheesy.
  • This recipe can be made gluten-free by using a gluten-free flour and breadcrumb mixture.
Slice of recipe on a white plate beside full casserole dish with potatoes and a spoon inside.

More Side Dish Recipes

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Potatoes Au Gratin

Tender sliced potatoes are in a cheesy sauce and coated with breadcrumbs.
Print Pin Recipe
Servings: 8 servings

Ingredients

  • 6 medium potatoes - yellow or russet
  • ½ yellow onion - sliced into thin strips
  • 3 Tbsp salted butter
  • 3 Tbsp all purpose flour - or gluten-free flour
  • ½ tsp salt
  • ¼ tsp ground pepper
  • 2 cups milk
  • 2 cups shredded cheese - 1 ½ cups for sauce, ½ cup for topping
  • ¼ cup breadcrumbs

Instructions

  • Preheat the oven to 375°F. Spray a baking dish with nonstick cooking spray.
    Casserole dish and cookign spray.
  • Slice the potatoes into thin slices. Slice the onion into thin strips.
    Sliced thin potatoes with a knife, and sliced thin onions with a knife.
  • Spread half of the potatoes in the casserole dish, layering as you go.
    Top with sliced onions.
    Add the last half of potato slices in a layer. Set aside for now.
    Three images of white casserole dish: first with layer of sliced potatoes, second with sliced onion on top, third another layer of sliced potatoes.
  • Heat the butter in a pot over medium-high heat, about 1-2 minutes.
    Melted butter in copper pot.
  • Add flour, salt and pepper and mix together until it's smooth and bubbly, about 1 minute.
    Two images: first with melted butter and flour, second with a thick sauce and spatula in copper pot.
  • Add the milk and bring it to a boil (will take 3-4 minutes) – stir often.
    Once boiling, stir frequently for 1 minute while it's bubbling, then remove from heat.
    Milky sauce mixture in a copper pot with a small spatula.
  • Add 1 ½ cups of the shredded cheese and mix together until melted, smooth and creamy.
    Two images: first with grated cheese in a sauce in copper pot, second with melted cheese and spatula in a copper pot.
  • Pour the sauce evenly overtop of the potatoes in casserole dish. Cover the dish with aluminum foil and bake for 1 hr 20 minutes.
    Two images: first with melted cheese over potatoes in white casserole dish, second with aluminum foil over dish and sitting on a baking sheet.
  • Remove the foil after 1 hour cooking. Sprinkle ½ cup cheese and breadcrumbs overtop and bake for additional 20-30 minutes, or until golden and crispy.
    Two images: first with melted cheese sauce overtop of sliced potatoes, second with breadcrumbs and cheese added on top.
  • Let cool 10 minutes, then dish on to plates to serve.
    Au gratin potatoes in a casserole dish, with a serving scooped on to a small plate beside.

Recipe Notes:

  • Scrub the potatoes and slice off any bruises / bad spots. Then slice each potato thin, about ½ thick. There’s no need for a mandoline slicer, however these are definitely handy if you have one.
  • It’s okay to use potatoes with small sprouts. These can be snapped off with your fingers or sliced off with a knife.
  • Potatoes should be completely dry before assembling the recipe. Pat them with a paper towel. This will produce crispier potatoes.
  • Lightly grease the casserole dish with nonstick cooking spray before adding potatoes.
  • While prepping the cheese sauce, stir constantly to avoid any burning.
  • Feel free to add more grated cheese with breadcrumbs to make it extra cheesy.
  • This recipe can be made gluten-free by using a gluten-free flour and breadcrumb mixture.
Nutrition
Calories: 308kcal | Carbohydrates: 37g | Protein: 12g | Fat: 13g | Saturated Fat: 8g | Polyunsaturated Fat: 1g | Monounsaturated Fat: 3g | Trans Fat: 1g | Cholesterol: 41mg | Sodium: 412mg | Potassium: 807mg | Fiber: 4g | Sugar: 5g | Vitamin A: 423IU | Vitamin C: 32mg | Calcium: 245mg | Iron: 2mg

Please note these nutritional values provided above are just an estimate. Actual numbers will vary based on brands and ingredients you choose, and your preferred portion sizes.

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