So you’ve been asked to bring the scalloped potatoes to the holiday meal. One-up the family recipe with these extra cheesy scalloped potatoes made from scratch. The velvety cream sauce, fluffy layers of baked potatoes, and bubbling cheesy top is going to make you want these for your dinner sidekick every night.
Working on this recipe got us wondering about the difference between scalloped potatoes and potatoes au gratin. Turns out, they’re close kin. First of all, gratin is always cheesy, while scalloped potatoes aren’t always made with cheese — but ours are, because cheese. Two kinds in fact. We used sharp cheddar and Parmesan, but you could make it three-cheese and add Gruyère, Swiss, or Asiago for a funkier note. Gratin is also sometimes topped with crispy browned breadcrumbs, but beyond that, they’re both creamy baked potato dishes that are guaranteed to get requests for seconds. So if you want to call these potatoes au gratin, go right ahead. (But we’re going to have to insist that you say it with a French accent.)
Don’t be discouraged by that mandoline slicer — you can totally slice the potatoes yourself with a sharp knife the way grandma did it. Our mandoline spends her days dreaming about the next date with Mr. Potato Head, and we love to get them together for our crispy potato roast, loaded potato casserole, and potato roses. That’s because a mandolin is a huge time saver when you need to turn a potato into a pile of paper-thin, even slices. The evenness is key, since it ensures that the potatoes bake at the same rate and you never have to endure the tragic experience of biting into a potato casserole and finding a mouthful that’s both mushy and crunchy. So the lesson is, if you do go old-school and use a knife, make sure you get the slices as even as you can.
About those taters: it actually matters what kind of potato you use. Shop for one that’s on the starchier side, like Yukon Gold (which we used) and russets. They hold their shape while baking, and their high starch content helps to make the sauce extra rich and creamy. Peels on or off? That’s up to you. (Peeled is the classic choice, but leaving the skins on will save you a step and give your scalloped potatoes a rustic look.)
We skipped the heavy cream in favor of whole milk since these are so dang cheesy. We also left out ham/bacon (which might be amazing) so that you can please everyone at the family table, including your vegetarian cousin. Now that aunt who used to be in charge of the scalloped potatoes? She might uninvite you to the next family gathering after she tries these. But don’t worry — everyone else will be rooting for you.
Prep Time: 20 Minutes
Total Time: 1 hour 30 Minutes
- 3 pounds Yukon Gold potatoes, peeled (optional) and sliced ⅛-inch thick
- 2 cup shredded sharp cheddar cheese, divided
- ½ cup grated Parmesan cheese
- 3 Tablespoons butter
- 1 medium onion, thinly sliced
- 4 cloves garlic, minced
- 3 Tablespoons all-purpose flour
- 3 cups whole milk
- 1 teaspoon kosher salt
- ½ teaspoon black pepper
- ¼ teaspoon grated nutmeg
- 1½ Tablespoons fresh thyme, divided
- Preheat the oven to 400°F / 205°C. Grease an 11-inch x 7-inch baking dish with butter and set aside.
- Using a mandoline slicer or a sharp knife, slice the potatoes to ⅛-inch thick. (If you’re using a knife, try to cut the slices as evenly as possible.
- Spread a third of the sliced potatoes in an even layer in the prepared baking dish.
- In a small bowl, combine the cheddar and parmesan cheese and mix them well. Reserve ¾ cup for the topping and set it aside.
- Prepare the sauce: in a large sauté pan over medium-high heat, melt the butter. Add the onion and cook until it’s translucent, about 4-5 minutes. Add the garlic and cook until it’s fragrant, about 30 seconds. Add the flour and stir while cooking for another 1 – 2 minutes. Add the milk, salt, pepper, nutmeg and 1 tablespoon of the thyme. Bring to a simmer and whisk until combined and thickened. Add the 1¾ cups of the cheese blend and stir until the cheese is melted and and the ingredients are completely mixed. Turn off the heat and set the sauce aside.
- Pour a third of the cheese sauce over the potatoes, and spread it out evenly with a spatula. Spread the next third of potatoes in the baking dish and top it with another third of cheese sauce. Repeat the layering process with the remaining potatoes and sauce. Top the final layer of sauce with the reserved ¾ cup of cheese.
- Cover the baking dish with foil and bake for 30 minutes. Remove the foil and bake uncovered for an additional 25 -30 minutes, or until the potatoes are cooked through and the sauce is bubbling. Sprinkle with the remaining fresh thyme and serve warm.