Cheesy Scalloped Potatoes (with garlic shallot thyme sauce)
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These scalloped potatoes are rich, creamy, and unapologetically cheesy, the kind of side dish that earns its place at the table every single time. Thinly sliced russet potatoes are layered with a silky sauce of garlic, shallots, and fresh thyme, then blanketed in Gruyère and Parmesan and baked until golden and bubbling at the edges.
These scalloped potatoes have been part of my family’s table for as long as I can remember, and I’ve made them more times than I can count. Over the years, I’ve been slowly tweaking it so the sauce-to-potato ratio feels exactly right and the cheese on top hits that perfect balance of melty and golden.
The sauce is what makes this recipe worth making over any other. I start by softening shallots and garlic in butter, then whisk in flour, whole milk, and cream to make a sauce that’s silky and rich without being heavy. Fresh thyme goes in early so it has time to bloom into the cream, and the whole thing comes together in about five minutes. The key is keeping it at a gentle simmer rather than a full boil — that’s what keeps the sauce smooth and prevents it from breaking or turning watery in the oven.
For the cheese, I use a combination of Gruyère and Parmesan. Gruyère melts beautifully and has a nutty, slightly sweet flavor that pairs perfectly with the creamy sauce, while Parmesan adds sharpness and helps the top get that deeply golden, slightly crispy finish I love.
The result is velvety and deeply satisfying, elegant enough for a holiday spread but simple enough that I’d make it on a regular Tuesday alongside a simple roast chicken. It’s also one of my favorite make-ahead sides, which I’ll get into below.
Scalloped potatoes vs. au gratin: what’s the difference?
Technically, traditional scalloped potatoes are made without cheese; they’re just thinly sliced potatoes baked in a cream sauce. Au gratin potatoes are the cheesy version, topped with breadcrumbs or cheese that get golden and crispy in the oven. In practice, most people use the terms interchangeably, and most recipes you’ll find called “scalloped potatoes” include cheese anyway.
This recipe lands firmly in au gratin territory, with two cheeses layered throughout and a golden, bubbly top. I still call them scalloped potatoes because that’s what my mom always called them, and honestly, that’s what most people are searching for when they want this kind of dish.
How to slice potatoes for scalloped potatoes
Having consistent, thin slices will mean your scalloped potatoes are tender and cook at the same rate. So, first things first, let’s talk about how thick scalloped potatoes should be. You’re aiming for ⅛ to ¼ inch thick slices. There are two ways to do this.
- With a mandolin: This is my favorite way! Simply set the thickness to ⅛ inch and go to town. Just remember to pop your safety guard on or wear some cut-resistant gloves.
- With a knife: For those of you without a mandolin, you can still get lovely potato slices, it’ll just take a teeny bit more time. First, grab a sharp chef’s knife, then slice them manually to around ⅛ inch thickness. I start this by slicing a small piece from the side of the potato to create a flat side, then I rest the potato on the flat part and slice away!
Variations of scalloped potatoes
This scalloped potato recipe is beautiful as it is, but I’ll occasionally make a variation to make it match whatever else I’m serving or just to mix it up. Here are some ideas:
- Add bacon or ham: Add some diced ham or crumbles of bacon between the layers for smoky, meaty scalloped potatoes.
- Add pesto: A spoonful of pesto adds a herby twist that pairs well with the creamy sauce.
- Cheese swap: If you want to use up whatever cheese is in the fridge or play with the flavors, add some sharp cheddar cheese, smoked gouda, or fontina.
Can you make scalloped potatoes ahead of time?
Yes, and I’d actually encourage it. They’re one of the best make-ahead sides I know. You have two options, depending on how far ahead you want to work.
If you’re making them the day before, assemble the whole dish, cover it tightly, and refrigerate it unbaked. When you’re ready, pull it out of the fridge about 30 minutes before baking to take the chill off, then bake as directed, adding 10 to 15 minutes to the covered baking time.
If you want to get a head start earlier in the day, you can also par-bake them: bake covered for the full 60 minutes, then let them cool and refrigerate. When it’s time to serve, bring them back to room temperature and finish with the uncovered bake and broil to get the top golden and bubbly again.
Cheesy Scalloped Potatoes (with garlic shallot thyme sauce)
Ingredients
- 2 tablespoons butter
- 2 medium shallots (very thinly sliced – see notes)
- 2 cloves garlic (finely minced)
- 1 ½ teaspoons sea salt
- 1 teaspoon EACH: black pepper and fresh thyme leaves
- 2 tablespoons all-purpose flour
- 2 cups whole milk
- 1 cup whipping cream
- 3 lb russet potatoes (peeled and thinly sliced)
- 1 cup grated gruyere (see notes)
- ½ cup grated parmesan
Instructions
- Preheat your oven to 400 degrees Fahrenheit. Melt the butter in a medium-sized pot over medium heat. Add the shallots and cook just until they turn translucent, about 3 minutes. Add the garlic, salt, pepper, and thyme and cook for 1 minute more. Stir in the all-purpose flour.2 tablespoons butter, 2 medium shallots, 2 cloves garlic, 1 ½ teaspoons sea salt, 1 teaspoon EACH: black pepper and fresh thyme leaves, 2 tablespoons all-purpose flour
- Whisk in the milk and cream, bring to a gentle simmer, and simmer for 2 minutes until it's thickened slightly.2 cups whole milk, 1 cup whipping cream
- Spread ⅓ cup of the sauce on the bottom of an 8" x 10" baking dish. Add the potatoes in a single, slightly overlapping layer and then sprinkle with a tiny bit of both cheeses.3 lb russet potatoes, 1 cup grated gruyere, ½ cup grated parmesan
- Pour ⅓ cup of the sauce over the top (don't worry if it doesn't cover the potatoes), and then add another layer of potatoes. Continue layering potatoes, cheese, and sauce. When you get to the last layer of potatoes, use your hands to gently flatten them down if they're a bit puffy in the middle. Then, pour the remaining sauce over the top, spread it around, and then sprinkle with the remaining cheese.
- Cover the baking dish tightly with foil and bake for 60 minutes.
- Remove the cover from the baking dish and bake for another 15 minutes. If you'd like more color, broil on low heat (see notes) for 5-10 minutes until the top starts to brown. Let the potatoes rest for at least 20 minutes before serving so they set up a little.
Video
Notes
Nutrition
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My family loved this!
Fantastic! Thanks, Katherine!
Delicious! I would add more salt and pepper, but that’s just me.
This recipe inspired me to finally purchase a Mandoline, and it made all the difference!
Yay for mandolins! I love mine too!
Can anything else be used instead of whipping cream, I have IBS an can’t have that cream.
I haven’t tried replacing it but I think using all milk will work just fine. It won’t be quite as rich, but it will still be very good!
I’ve made these delicious scalloped potatoes and am sooo very happy how they turned out. As you can see, I like a little browned topping mmmmmm
My husband (& I) and our guests came back for 2nds, & 3rds!
They look fabulous! You’re making me hungry!!