Preheat oven to 400° F. Slice potatoes very thinly (⅛ inch or thinner). This is easiest with a food processor or mandolin, but you can certainly do it by hand. Pat slices dry so they crisp on the outside. Heat a large (I used a 12-inch) ovenproof skillet over medium-high heat. Add 2 tablespoons clarified butter; swirl to coat. Arrange some potatoes in concentric circles.

Season with ¼ teaspoon salt and some freshly ground pepper to coat.

Repeat with remaining potatoes to form 2 more layers. Pour 3 tablespoons clarified butter down sides of skillet to seep under potatoes. At this point, you want to weigh down the potatoes to encourage them to bind together. The first time we disregarded this step and just covered with a regular lid, and while everything worked out, it did make the pancake harder to work with. The second time, I set a piece of buttered parchment paper over the potatoes and set a regular pot lid that was the same diameter as the pancake on top and weighted it down with whatever was lying around. Reduce heat to medium or medium low. Cook until underside is golden and crisp, 5 to 7 minutes more. Flip potatoes (if you went small, this is no big deal. If you went big, you may need to employ 2 spatulas or get creative with your utensils. Also, as you can see in the photo, it cooked a little unevenly, the weight helps with this as well).

Weight back down. Cook until potatoes start to brown, about 4 minutes. Remove weights and expose to air. Bake until underside is crisp, 7 to 9 minutes. While that’s cooking, whisk the mascarpone, crème fraîche, lemon zest, and dill until it’s light and fluffy.

Set aside. Let pancake cool for 10 minutes. If you want to let some butter drain off, and keep maximally crisp, use a wire cooling rack, or let it cool in the pan. Set on serving plate. So gorgeous!

Spread the seasoned cream mixture over the potato pancake. Top with salmon. Sprinkle with chives. Cut into wedges (a pizza cutter worked well here).  Cedar Kitchenette photo credit on this one.

Serve immediately while the cream is a little melty.