Rock salt, for baking
Two 12-ounce Yukon Gold potatoes
1 cup all-purpose flour, plus more for dusting
2 large eggs, lightly beaten
2 1/2 teaspoons kosher salt
1 tablespoon extra-virgin olive oil, plus more for drizzling
3 tablespoons unsalted butter
1 medium onion, minced
1 celery rib, minced
6 ounces sliced pastrami, finely chopped (1 1/2 cups)
1 cup water
1 cup low-sodium chicken broth
1/4 cup sour cream
1/4 cup sliced chives