This is the creamy, cheesy potato side dish that disappears first at every holiday table and Sunday dinner. Easy scalloped potatoes layer thinly sliced russet potatoes in a rich, savory cheese sauce made with Parmesan and Asiago, then bake until the top is golden brown and the potatoes are meltingly tender. The sauce is built on a simple roux with onion and garlic, so it’s silky and full of flavor, and the whole thing comes together with just a handful of ingredients. It’s comfort food at its finest, the kind of side that goes with everything from a holiday ham to a weeknight roast chicken.
The secret to great scalloped potatoes is in the details: a proper cheese sauce that coats every slice, potatoes cut thin and even so they cook through perfectly, and enough time in the oven to turn golden and bubbly on top. This version keeps it approachable, with clear steps and a from-scratch cheese sauce that’s easier than it sounds. Tender potatoes, creamy sauce, and a browned, cheesy top, it hits all the right notes.
Why this works
A few key techniques are what make these potatoes turn out creamy and evenly cooked, and they’re worth understanding.
The cheese sauce starts with a roux, which is the foundation of a smooth, thick sauce. Cooking the onion in butter, adding garlic, then stirring in flour creates a paste that thickens the milk as it cooks, so you get a rich, velvety sauce rather than a thin, watery one. Bringing the milk to a boil and cooking it until it coats the back of a spoon (about the thickness of alfredo) is the key, properly thickened sauce is what makes the dish creamy rather than runny. Stirring in Parmesan and Asiago adds sharp, nutty, savory flavor.
The single most important step, and the recipe is right to emphasize it, is slicing the potatoes uniformly. If some slices are thick and some thin, they cook unevenly, leaving you with mushy spots and crunchy spots. Thin, even slices (a mandoline makes this easy and fast) cook at the same rate, giving you perfectly tender potatoes throughout.
Russet potatoes are the right choice here for a reason: their starch helps thicken the sauce as it bakes. That’s also why you shouldn’t rinse the sliced potatoes, the natural surface starch is a benefit. (If you slice them ahead, keep them in cold water to prevent browning, then drain and pat dry before layering.)
And layering matters. Alternating sauce, potatoes, and cheese in layers, and gently pressing each layer down to eliminate air pockets, gives the dish good structure and ensures every bite has sauce. Baking uncovered is what lets the top brown beautifully.
What goes in
The ingredient list is short and built from staples.
You’ll need unsalted butter, a yellow onion, garlic, all-purpose flour, whole milk, grated Parmesan, shredded Asiago, russet potatoes, and salt and pepper.
A few notes. Use russet potatoes for their starch (which helps thicken the sauce) and slice them thin and even. Use whole milk for the richest sauce. Parmesan and Asiago give a sharp, nutty flavor, but you can use other good melting cheeses (Gruyère, cheddar, or a mix) if you prefer. And if you’d rather, oil can replace the butter in the roux. A mandoline is the easiest way to get uniform slices.
How to make them
Preheat your oven to 350°F.
Make the cheese sauce first. Melt the butter in a medium pot over medium heat, then add the diced onion and cook, stirring often, until lightly browned, about 5 minutes. Stir in the garlic and cook just until fragrant, 20 to 30 seconds. Mix in the flour to form a roux.
Pour in the milk and bring it to a boil over high heat, stirring, until it thickens to the consistency of alfredo sauce and coats the back of a spoon. Stir in half of the cheeses, plus salt and pepper to taste.
Now assemble. Spread about a third of the cheese sauce in the bottom of a 7×11 casserole dish coated with non-stick spray. Layer on half the potatoes, half the remaining cheese, and another third of the sauce. Then add the rest of the potatoes, followed by the remaining sauce and cheese. Gently press the layers down as you go to remove air pockets.
Bake uncovered at 350°F for about 1 hour, until the top is well browned and the potatoes are tender when pierced. Let it rest a few minutes, then serve.
Tips, make-ahead, and storing
A few things make the difference. Slice the potatoes uniformly (a mandoline helps) so they cook evenly, the number one tip for great scalloped potatoes. Cook the sauce until it’s properly thick before assembling. Don’t rinse the potatoes, since their starch helps the sauce thicken as it bakes. And press the layers down to eliminate air pockets for a better structure.
A couple more. If the top browns too fast before the potatoes are tender, loosely tent it with foil for the rest of the baking time. And letting the dish rest for 5 to 10 minutes after baking helps it set up so it slices and serves more neatly rather than running.
These are great for making ahead, which is perfect for holidays. To prep ahead, follow all the steps but bake for only 35 to 40 minutes. On the day you want to serve, cover with foil and bake 15 minutes covered, then uncover and bake another 15 minutes at 350°F until perfectly cooked and hot through.
For storing, cover and refrigerate for up to 4 days. To reheat, place portions in a small pan and bake at 350°F for 6 to 8 minutes, until warmed through. They also freeze well covered for up to 3 months, just thaw in the refrigerator for a day before reheating.
This serves about 6 as a side. Creamy, cheesy, tender, and golden on top, these easy scalloped potatoes are a comforting classic that earns a spot at any special meal, and they pair beautifully with just about any main you can think of.
WP Tasty (Tasty Recipes Premium) field values
- Category: Side Dish
- Method: Baking
- Cuisine: American
- Diet: (leave blank. It contains wheat (flour) so it isn’t gluten-free, and it’s only “vegetarian-ish”: Parmesan and Asiago are traditionally made with animal rennet, so they aren’t strictly vegetarian, look for rennet-free cheeses if that matters. Use a gluten-free flour to make the roux gluten-free.)
- Keywords: easy scalloped potatoes, scalloped potatoes, cheesy scalloped potatoes, creamy scalloped potatoes, potato side dish
- Serving Size: 1 serving (recipe serves 6)
- Calories: 296 (from source; full nutrition is in the JSON.)
- Equipment: Medium pot, 7×11 casserole dish, mandoline (optional)
Easy Scalloped Potatoes
Equipment
- Medium pot
- 7×11 casserole dish
- Mandoline (optional)
Ingredients
- 3 tbsp unsalted butter
- 1 yellow onion peeled and small diced
- 1 clove garlic finely minced
- 2 tbsp all-purpose flour
- 2 cups whole milk
- 1/2 cup grated parmesan cheese
- 1/2 cup shredded asiago cheese
- 4 russet potatoes peeled and thinly sliced
- salt and pepper to taste
Instructions
- Preheat: Preheat the oven to 350°F.
- Start the Sauce: Melt the butter in a medium pot over medium heat. Add the onion and cook, stirring often, until lightly browned, about 5 minutes. Stir in the garlic and cook until fragrant, 20 to 30 seconds. Mix in the flour to make a roux.
- Thicken: Pour in the milk and bring to a boil over high heat, stirring, until thick like alfredo sauce and it coats the back of a spoon. Stir in half the cheeses, plus salt and pepper.
- Layer: Spread 1/3 of the sauce in the bottom of a greased 7×11 casserole dish. Add half the potatoes, half the remaining cheese, and another 1/3 of the sauce. Top with the remaining potatoes, then the remaining sauce and cheese, gently pressing the layers down.
- Bake: Bake uncovered at 350°F for about 1 hour, until well browned on top and tender. Rest a few minutes, then serve.
