Remember those pink salt blocks everyone was searing steaks on for a minute? A bit of kosher salt performs a similar function: transmitting heat.

2 cups kosher salt

1 1/2 pounds fingerling potatoes

2 sprigs rosemary

3 garlic cloves, thinly sliced

1/4 cup olive oil

Flaky sea salt

Preparation Preheat oven to 425°F. Spread kosher salt in a 13x9" baking dish. Scrub potatoes, pat dry, and poke a few holes into each; arrange over salt. Roast until flesh is very tender and skins are crisp, 30–40 minutes. Meanwhile, strip leaves from rosemary sprigs and cook with garlic and oil in a small saucepan over medium-low heat, swirling pan occasionally, until garlic is golden, about 3 minutes. Transfer to a large bowl and add potatoes; toss to coat. Serve potatoes generously sprinkled with sea salt.