Much like green bean casserole and angel biscuits , scalloped potatoes belong on Southern dinner tables. The rich, tender, creamy potato casserole is elegant enough for a nice holiday dinner but also humble enough for a weeknight meal, family dinner, or reunion potluck.
With fewer than 10 ingredients on the list, this also isn't a fussy recipe. In fact, the most complicated aspect of this scalloped potatoes recipe is getting the potatoes sliced thinly.
We recommend using a mandoline slicer. It makes cutting uniform slices of potatoes and other vegetables incredibly easy. Just be sure to use the guard or a cut-resistant glove to protect your fingertips.
If you don't have a mandoline, use your sharpest kitchen knife, and try to cut slices as close to the same size as possible. This way, they cook evenly, and you won't have some underdone slices while others are tender.
How to Make Scalloped Potatoes
Prep the pan: To make this recipe for scalloped potatoes, first preheat the oven to 400°F, and lightly coat a baking dish with cooking spray.
Make the sauce: Melt butter into a saucepan, adding flour and cooking while stirring constantly until a paste forms and bubbles (but does not brown). Whisk in milk and bring it to a boil.
Reduce the heat, and whisk in nutmeg and salt. Cook while whisking until thickened before removing from the heat and setting aside.
Sauté onion: Heat the remaining butter in a nonstick skillet, and add onion, thyme, and salt.
Cook until softened, and remove from heat.
Build the casserole: Add one-third of the potatoes to the prepared baking dish in a single layer. Top with half of the onion mixture and one-third of the cream sauce, and repeat the layers until finished, ending with the cream sauce on top.
Cook the casserole: Bake, covered, for 30 minutes. Uncover, and continue to bake until bubbly and golden brown, about 20 to 25 more minutes. Remove from the oven, and let stand for 10 minutes before serving.
What Is the Difference Between Scalloped and Gratin Potatoes?
While both scalloped potatoes and au gratin potatoes typically use heavy cream, flour, and butter for a rich texture and flavor, only au gratin potatoes also contain grated cheese.
The culinary term gratin refers to the method of baking or broiling with a grated cheese and breadcrumb-based topping for a crispy result.
What Are Scalloped Potatoes Made Of?
This scalloped potato recipe begins with Yukon Gold potatoes. The richness of the sauce comes from all-purpose flour, whole milk, and butter. Ground nutmeg, kosher salt, yellow onion, and fresh thyme leaves round out the flavors.
What Does It Mean to Scallop Potatoes?
Scalloped potatoes are sliced thinly, layered, and cooked in a creamy sauce with flour, cream, and butter.
What Do Scalloped Potatoes Taste Like?
In this recipe, scalloped potatoes are tender with a sauce that is creamy, rich, and decadent. The onion imparts a slightly sweet flavor.
Can Potatoes Be Sliced Ahead of Time for Scalloped Potatoes?
Scalloped potatoes make an ideal holiday side dish —and you can begin the prep the day before serving to manage your time in the kitchen. Potatoes can be peeled about 24 hours ahead of time.
As soon as you peel them, fully submerge the potatoes in a bowl of water. This will keep them from the discoloration that occurs when they come in contact with the air.
Editorial contributions by Alesandra Dubin .
6 Tbsp. (3 oz.) unsalted butter, divided
½ cup (about 2 1/8 oz.) all-purpose flour
2 ½ cups whole milk
¼ tsp. ground nutmeg
2 tsp. kosher salt, divided
1 large (12 oz.) yellow onion, thinly sliced (about 2 1/2 cups)
1 tsp. fresh thyme leaves
1 ½ lb. Yukon Gold potatoes (about 3 large potatoes), scrubbed, cut into 1/8-in.-thick slices
Preheat oven to 400°F. Lightly coat an 11- x 7-inch baking dish with cooking spray.
Melt 4 tablespoons of the butter in a medium saucepan over medium. Add flour, and cook, stirring constantly with a wooden spoon, until a paste forms and bubbles, 1 to 2 minutes (do not let it brown). Whisk in milk, and bring to a boil over medium, whisking often. Reduce heat to medium-low; whisk in nutmeg and 1 1/2 teaspoons of the salt. Cook, whisking occasionally, until thickened, 2 to 3 minutes. Remove from heat, and set aside.
Heat remaining 2 tablespoons butter in a large nonstick skillet over medium. Add onion, thyme, and remaining 1/2 teaspoon salt; cook, stirring occasionally, until softened, about 15 minutes. Remove from heat.
Add one-third of the potatoes to the bottom of the prepared baking dish in a single layer. Top with half of the onion mixture (about 2/3 cup) and one-third of the cream sauce (about 2/3 cup). Add one-third of the potatoes, remaining onion mixture, and one-third of the cream sauce. Add remaining potatoes, and top with remaining cream sauce.
Cover, and bake in preheated oven for 30 minutes. Uncover, and bake until bubbly and golden brown, 20 to 25 minutes. Remove from oven, and let stand 10 minutes. Serve.