Creamy and cheesy with a golden topping, this sweet and savory scalloped sweet potatoes with gruyere cheese is perfectly balanced in a herbed cream sauce.
Preheat the oven to 400 degrees F. Spray a 9x13-inch baking dish with cooking spray; set aside.
Use a mandolin to slice the sweet potatoes into ⅛-inch thick slices. Arrange them in even, alternating layers in the baking dish.
Melt the butter in a saucepan set over medium-high heat. Add in the garlic, thyme, salt, pepper, and nutmeg and saute for 30 seconds, until fragrant. Remove the pan from the heat.
Whisk in the heavy cream, ¼ cup Gruyere, and Parmesan until smooth and creamy. Pour the mixture over the layered sweet potatoes. Sprinkle the remaining Gruyere over the top.
Bake for 50-60 minutes or until the sweet potatoes are tender. Broil on high for 1-2 minutes at the end, until golden brown.
Notes
Slice potatoes into thin even rounds, using a mandolin slicer if possible, for even cooking. Use dried herbs as they maintain their texture and flavor during baking.Broil for the last 1-2 minutes for a golden topping.Check for doneness by inserting a sharp knife into the potatoes to be sure they are cooked through and tender.