Preheat the oven to 350°F (180°C). Line 3 baking sheets with parchment paper.
On a lightly floured work surface, using a floured rolling pin, roll the dough into a 16-by-12-inch (40-by-30-cm) rectangle about ¼ inch (6 mm) thick. Starting at the short end closest to you and using an offset spatula, evenly spread 1 cup (10oz/310g) of the jam over half of the dough, leaving a ½-inch (12-mm) border. Starting at the end covered in jam, roll up the dough tightly until you reach the center point of the dough forming a log.
Carefully invert the dough, flipping the log so that the long portion of dough not covered in jam is on your right and the rolled log is now on your left. Evenly spread the remaining 1cup of jam onto the other half of the dough. Roll up the dough, tightly forming a log, until you reach the center of the dough. The two rolls should be rolled up in opposite directions, meeting in the center. Gently press the two rolls together. Use a chef’s knife to trim the uneven ends. Refrigerate or freeze the log until firm, about 10 minutes.
Using a sharp knife, cut the roll crosswise into 30 slices about ½ inch thick. Use a metal spatula to transfer the slices to the prepared sheets, spacing them 1½ inches (4 cm) apart. Sprinkle each cookie with sugar.
Bake the cookies until lightly golden around the edges and the tops are barely colored, 16—19 minutes. Let cool completely, about 30 minutes.
Store the cookies in an airtight container, layered between sheets of parchment paper, at room temperature for up to 4 days.