by Susie Middleton
- 3 Tbsp. plus 1⁄2 tsp. extra-virgin olive oil
- 1 1⁄2 lbs. Yukon Gold potatoes (about 4 medium)
- 1 1⁄2 tsp. chopped fresh rosemary
- 3⁄4 cup grated Gruyere cheese
- 1/3 cup finely grated Parmigiano Reggiano
- kosher salt
Heat the oven to 375° and arrange one rack in the middle of the oven. Rub a 9-inch tart pan or a 9 1⁄2-inch cheesecake pan with 1⁄2 tsp. of the olive oil. (Make sure the pan has a removable bottom.)
Put the potatoes on your cutting board and trim a small slice off the bottom of each to stabilize it. Trim off and discard the very ends of the potatoes. Then cut the potatoes crosswise into very thin slices. Use a sharp, thin-bladed (but strong) knife—a Santoku knife works great for cutting thin potato slices. Slice as thinly as you can, but don’t worry in the least if the slices are inconsistent; the galette will still cook evenly as long as you don’t include any really thick slices. If you have a mandolin, you can certainly use it, but you don’t need to.
Put the potato slices, the chopped rosemary, and the remaining 3 tbsp. of olive oil into a mixing bowl and toss thoroughly to coat.
Cover the bottom of the pan with a layer of potato slices, starting by making a ring of slightly overlapping slices all the way around the outside edge, and then working inward, laying down more rings of slightly overlapping slices until the bottom is covered. Sprinkle the potatoes with a tiny bit of kosher salt (about 1/8 tsp) and then sprinkle about 1/3 of the Gruyere and 1/3 of the Parmigiano over all. Arrange another layer of potatoes over that, season again with salt, sprinkle with 1/3 of each cheese again, and finish with a top layer of potatoes and cheese.
Bake the galette until the top is golden brown and a fork easily pierces the layers of potato, about 45 to 50 minutes. Let the galette cool for 10 to 15 minutes in the pan. Run a thin knife around the edge to unstick any cheese and remove the cheesecake ring or the tart ring, leaving the galette on the bottom of the pan. Use a thin spatula to gently release the galette from the pan bottom, and transfer the galette to a cutting board. Cut into 6 or 8 pie-shaped pieces. Serve warm.
Serves 6 to 8