Transfer the dough to a heavily floured work surface and generously dust the top of the dough with additional flour. Flatten the dough into an 6-inch square with your hands or a rolling pin. Gently flip the dough to keep it from sticking, flour it again, and flatten the dough into a ¼-inch-thick square. With a floured pizza cutter or sharp knife, cut the dough into long ½-inch-wide strips, and then cut the strips into ¾-inch-long rectangles on the opposite axis. Transfer the dumplings to a wax or parchment paper-lined baking sheet.