Tartiflette

Step 1

Peel potatoes and cut into 1/2-inch thick rounds. In a large pot, cover potatoes with cold water. Season generously with salt, add thyme, and bring to a gentle simmer over medium heat. Cook at a bare simmer until potatoes are just tender and can easily be pierced with a paring knife, about 25 minutes. Discard thyme, drain potatoes, return to pot, and set aside.

Step 2

Adjust oven rack to middle position and preheat oven to 350°F (175°C). In a 10-inch cast iron or stainless-steel skillet, heat bacon over medium-high heat until fat begins to render. Lower heat to medium and continue to cook, stirring occasionally, until fat is mostly rendered and bacon is cooked but not crisp, about 5 minutes. If there is excessive rendered fat, drain off all but 1/4 cup (60ml); conversely, if the bacon is lean and didn't release much fat, add 1 to 2 tablespoons (15 to 30g) butter. Add onions, season with salt and pepper, and cook, stirring frequently, until onions have softened but not browned, about 8 minutes.

Step 3

Add white wine and cook, stirring, until wine has almost fully cooked off, 1 to 2 minutes. Scrape bacon-onion mixture into pot with potatoes and toss gently to thoroughly combine.

Step 4

Scrape potato mixture back into cast-iron skillet or into a 3-quart (3L) baking dish. Add cream or crème fraîche (the latter is thicker, so you can dollop it around in that case).

Step 5

Cut cheese into roughly 1/2-inch-thick slabs. You can do this by cutting the cheese wheels in half to make half-moons; halve wheels through the equator; or slice crosswise into thick planks. Arrange cheese on top of potatoes, rind side up. Set skillet or baking dish on top of a rimmed baking sheet and bake until the cheese is melted and bubbling and lightly browned on top, about 40 minutes.

Step 6

Serve, scooping tartiflette from the skillet or baking dish onto individual serving plates.