Hasselback Potato Gratin
- 3 ounces finely grated Gruyère or comté cheese
- 2 ounces finely grated Parmigiano-reggiano
- 2 cups heavy cream
- 2 medium cloves garlic, minced
- 1 tablespoon fresh thyme leaves, roughly chopped
- Kosher salt and freshly ground black pepper
- 2 1/2 pounds russet potatoes, peeled and sliced 1/8th-inch thick on a mandoline slicer (about 5 medium)
- 2 tablespoons unsalted butter
Preparation time 15mins
Cooking time 120mins
Adapted from seriouseats.com
Adjust oven rack to middle position and preheat oven to 400°F. Combine cheeses in a large bowl. Transfer 1/3 of cheese mixture to a separate bowl and set aside. Add cream, garlic, and thyme to cheese mixture. Season generously with salt and pepper. Add potato slices and toss with hands until every slice is coated with cream mixture, making sure to separate any slices that are sticking together to get the cream mixture in between them.
Grease a 2-quart casserole dish with butter. Pick up a handful of potatoes, organizing them into a neat stack, and lay them in the casserole dish with their edges aligned vertically. Continue placing potatoes in casserole, working around the perimeter and into the center until all potatoes have been added. Pour excess cream/cheese mixture evenly over potatoes.
Cover tightly with foil and transfer to oven. Bake for 30 minutes. Remove foil and continue baking until top is pale golden brown, about 30 minutes longer. Carefully remove from oven, sprinkle with remaining cheese, and return to oven. Bake until deep golden brown and crisp on top, about 30 minutes longer. Remove from oven, let rest for a few minutes, and serve.