Potato Rolls With Caraway Salt

Name: Potato Rolls With Caraway Salt
Ingredients: 1 8-ounce russet potato, peeled, cut into 1 pieces; 4 tablespoons (1/2 stick) unsalted butter plus more for the bowl and pan; 1 cup whole milk; 2 tablespoons sugar, divided; 1 1/2 teaspoons kosher salt, divided; 1 1/4-ounce package (2 1/2 teaspoons) active dry yeast; 3 3/4 cups (or more) all-purpose flour, divided, plus more for surface; 1 teaspoon toasted caraway seeds, lightly crushed; 1 teaspoon pretzel salt or sea salt; 1 large egg; 2 teaspoons heavy cream