French onion scalloped potatoes need to make an appearance on your dinner table! 

french onion scalloped potatoes

Yessss I am the crazy person serving you another french onion recipe! This time, in your scalloped potatoes. 


Caramelized, thyme-studded onions are swirled into super cheesy sliced potatoes. Lots of melty gruyere, just to hit the classic french onion taste.


caramelized onions in a skillet

Really, I know that I say this every single time, but I have to be close to the end of the french onion obsession. I mean, is there even anything else I can french onion? I’ve french onion-ed all the things. Promise we’re near the end.

In the meantime, just enjoy all this caramely, cheesy goodness.

I know that I sure am. 

layering potatoes, sauce and caramelized onions

If you’re looking for Easter menu ideas, I’ve got you! This is a dish you can add to your table that would be an absolute showstopper. 

I’ve shared these asiago scalloped potatoes before, with both white potatoes and sweet potatoes! They are super good.

This version is similar, just with lots of delicious, savory caramelized onions. The depth of flavor is incredible.

layer potatoes, gruyere, caramelized onions

My mom makes the best scalloped potatoes and they are one of Eddie’s favorite dishes. She only tends to make them on Easter, because she also has an arsenal of other amazing potato dishes she makes regularly. And every year when she makes them, we’re all always like WHYYYY DO WE ONLY HAVE THESE ONCE A YEAR?!

It’s mind blowing, because they are so incredible. And they reheat well, they travel well, really you can’t go wrong.

french onion scalloped potatoes

I think the main issue is that scalloped potatoes can be a bit high maintenance. You have to slice the potatoes, make the sauce, grate the cheese – all that jazz. And here I am, making them even more high maintenance, because I’m demanding that you caramelize onions for an hour before. 

Or heck, at least 40 minutes. Real caramelized onions take awhile, even though most of the time is hands off. You just need to sit even now and then. 

Once you make a batch of caramelized onions, the rest is scalloped potato history. I like to use a mandolin for the best even results, but you can also thinly slice potatoes. You can do this the night before, just store them in a bowl of ice water in the fridge overnight!

french onion scalloped potatoes

I like to use gruyere cheese here because it’s the classic flavor of french onion soup. I throw some in the cheese sauce and some in between the layers, along with the caramelized onions. Top the entire thing off with crunchy breadcrumbs, bake until it’s melting together and the potatoes and super soft. 

The cheese is golden and bubbly.

They are irresistible! 

If you love making a good casserole or dinner dish for your family, whether it’s for a holiday or even sunday dinner, this is it. Yes, it’s a labor of love, but the end result is so wonderfully worth it. 

french onion scalloped potatoes

French Onion Scalloped Potatoes

French Onion Scalloped Potatoes

These french onion scalloped potatoes are a little twist on the classic! Caramelly, thyme onions are swirled into cheesy sliced potatoes.
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  • 4 tablespoons unsalted butter
  • 4 tablespoons all-purpose flour
  • 3 ½ cups milk
  • kosher salt and pepper
  • ¼ teaspoon freshly grated nutmeg
  • 12 ounces freshly grated gruyere cheese
  • cup seasoned bread crumbs


  • Preheat the oven to 375 degrees F.
  • Thinly slice the onions. Heat the 4 tablespoons of butter in a skillet over medium heat. Add in the onions with a big pinch of salt and pepper. Stir. Cook for 10 minutes, stirring occasionally, until the onions soften. Reduce the heat to medium-low, stir in the thyme and cook for another 30 to 40 minutes, stirring often, until the onions are golden and caramelly in color. If at any time the onions start to burn, turn down the heat or add a splash of water to the pan. If the onions are not cooking, you need to raise the temperature a bit.
  • Use a mandoline or sharp knife to thinly slice the potatoes - you want them to be very thin, uniform in size and ⅛ inch thick or thinner. If you are slicing them ahead of time or with a while to go before assembling, place them in a bowl of ice water so they don’t brown.
  • Make the sauce! Heat the other 4 tablespoons of butter in a saucepan until melted. Whisk in the flour to create a roux. Cook for 2 to 3 minutes, stirring, until the roux is golden in color and smells fragrant and nutty. Slowly stream in the milk while whisking the entire time, bringing the sauce together.
  • Continue to stir the sauce and whisk in a pinch of salt and pepper and the nutmeg. Reduce the heat to low. Slowly stir in 6 ounces (about half) of the gruyere until melted. Taste and season with more salt and pepper if needed.
  • Layer half of the potatoes in the baking dish. Cover with half of the cheese sauce, then half of the caramelized onions and half of the remaining grated gruyere. Layer the remaining potatoes on top. Top with the remaining cheese sauce, covering all the potatoes. Top with the remaining caramelized onions and the grated gruyere. Top with the bread crumbs.
  • Bake uncovered for 45 to 60 minutes, or until the potatoes are tender enough to pick up with a fork. If the top gets too brown towards the end, you can tent it with foil. Let cool slightly before serving.

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french onion scalloped potatoes

Such cheesy goodness.