Crispy Potato Dauphinoise Recipe

Prep and slice potatoes

Preheat oven to 350°F (175°C). Using a mandoline or a very sharp knife, slice the peeled potatoes 1/16"–1/8" (about 1.5–3 mm) thick. Put the slices into cold water to remove excess surface starch, then drain and pat dry thoroughly with a clean towel.

Infuse cream

In a medium saucepan, combine the heavy cream, milk, smashed garlic cloves, 1 tablespoon butter, thyme (if using), 1 teaspoon kosher salt, and 1/2 teaspoon freshly ground black pepper. Warm gently over medium-low heat until small bubbles form around the edge (do not boil). Remove from heat and let steep for 10 minutes to infuse the garlic and thyme. Remove and discard the garlic cloves.

Assemble

Butter a 9-inch ovenproof skillet or shallow gratin dish with 1 tablespoon butter. Arrange a single overlapping layer of potato slices in the bottom so they lie flat; season lightly with a pinch of salt and pepper. Sprinkle a thin layer (about 2 tablespoons) of Gruyère. Repeat layering potatoes, seasoning, and cheese until all potato slices are used, finishing with a light sprinkle of Gruyère and the Parmesan on top.

Pour cream and bake

Carefully pour the warm cream mixture over the layered potatoes until it just comes to the top of the potato stack (do not submerge completely; leave a little headspace). Cover tightly with foil and bake at 350°F (175°C) for 45 minutes. Remove foil and continue baking for another 20–25 minutes, or until cream is bubbling and potatoes are tender when pierced with a knife.

Rest

Remove the dish from the oven and let it rest uncovered for 10 minutes. This helps the cream set slightly so the slices hold together for crisping and plating.

Create crispy top or individual rounds

For a restaurant-style crispy finish, slice the dauphinoise into 6 wedges or lift out portions and press gently into individual rounds (about 3" diameter) using a round cutter or spoon. Heat a large nonstick skillet over medium-high heat. Add the vegetable oil and 1 tablespoon butter and let the butter foam. For each portion, place the cut face down in the skillet and cook 2–3 minutes until a deep golden crust forms. If crisping the whole top instead, brush lightly with oil and place under a high broiler for 2–4 minutes watching carefully until deeply golden and bubbly.

Drain and season

Transfer crisped portions to a paper-towel lined tray for 30 seconds to remove excess oil. Sprinkle a light pinch of flaky sea salt over each portion while still hot.

Prepare sour cream

Whisk the chilled sour cream briefly to smooth it. Taste and season very lightly with a tiny pinch of salt if needed; caviar is salty so keep seasoning minimal.

Plate and finish

Place a crisped potato dauphinoise portion on each plate. Dollop about 1 tablespoon of sour cream onto each portion (or pipe a small quenelle). Gently spoon approximately 1/6 oz (about 5 g) of Osetra Royale caviar over the sour cream. Sprinkle 1 teaspoon of finely snipped chives across each portion and finish with a few flakes of sea salt around the plate if desired. Serve immediately so the crisp remains crisp and the caviar cool and restorative.