This holiday side takes everything you love about a traditional potato gratin — the bath of butter and cream — and tweaks it to play off the flavors of sweet potatoes. A bit of thyme and nutmeg are added to bring out the savory side of sweet potatoes, and sprinkle of nutty Gruyère cheese tops the dish before it goes into the oven.
If you're looking for a new tradition on your Thanksgiving table this year, consider this a contender.
Something Old and Something New
If your family is like mine, Thanksgiving dinner is a very fine balance between carefully introducing new side dishes to the table, while keeping those who love the tried-and-true classics happy. Often the trick to a new side is keeping an element of familiarity, while only changing one or two things. And that's what this dish does.
Expect the same rich experience of thin slices of potatoes gently cooked in a fragrant cream sauce, except this recipe features sweet potatoes, and the cream mixture is scented with garlic, thyme, and nutmeg.
Thin Slices of Potato Work Best
While there's no need to worry about perfectly round slices of sweet potato, do be mindful of the thickness of slices. I recommend slicing the potatoes 1/4-inch thick, but no thinner. It's just thick enough for the sweet potatoes to cook through and soften, soaking up the richness of the cream and butter, without becoming too soggy or falling apart.
Scalloped Sweet Potatoes
Cooking spray or butter
2 cups heavy cream
2 tablespoons unsalted butter
2 cloves garlic, minced
1 bay leaf
1 teaspoon fresh thyme leaves
1/4 teaspoon ground nutmeg
1 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
3 pounds sweet potatoes (about 4 to 5 medium), peeled and sliced into 1/4-inch thick rounds
1/2 cup shredded Gruyère cheese
Arrange a rack in the middle of the oven and heat to 400°F. Grease a 9x13-inch baking dish with butter or cooking spray; set aside.
Place the cream, butter, garlic, and bay leaf in a small saucepan and bring to a simmer over low heat. Meanwhile, combine the thyme, nutmeg, salt, and pepper in a small bowl.
Evenly distribute about half of the potatoes over the bottom of the baking dish. Sprinkle with half of the salt and herb mixture. Add the remaining potatoes in an even layer. Sprinkle with the remaining seasoning.
Remove the bay leaf from the cream and discard. Pour the cream and garlic over the potatoes. Push down to submerge them as much as possible. The potatoes won't be fully submerged — that's okay. Cover tightly with aluminum foil.
Bake for 15 minutes. Uncover and bake until the sweet potatoes are tender, about 15 minutes more. Remove the baking dish from the oven. Turn on the oven's broiler. Sprinkle the cheese over the top of the potatoes. Broil until the cheese is melted and the top is lightly browned, 3 to 5 minutes. Let the sweet potatoes cool for about 10 minutes before serving.
- Storage: Leftovers can be stored in an airtight container in the refrigerator for up to 3 days.