Preheat oven to 350° and line 2 baking sheets with parchment paper. Divide dough in half; rewrap one half and return to refrigerator.
On a lightly floured surface, roll out dough to a 10"-by-8" rectangle. Cut in half lengthwise to yield 2 (10"-by-4") strips. (Dough will be slightly sticky; you can roll out between 2 sheets of plastic wrap or parchment paper, if desired.)
Spread 1/2 cup filling down the center of a strip, making sure filling is evenly distributed and goes right to the edges of dough. Fold one long side of dough strip over filling, then continue to roll strip over so dough encloses filling in a long log. Repeat with second dough strip and another 1/2 cup filling, then cut each log into 8 pieces. Arrange pieces on prepared baking sheets.
Bake until light golden brown around the edges and tops are dry, 13 to 17 minutes. Transfer cookies to a wire rack and let cool completely. Repeat with remaining dough and filling.
In a small bowl, stir powdered sugar and lemon juice. Add more lemon juice, 1 teaspoon at a time, until glaze reaches a smooth, pourable consistency.
Spoon glaze over cooled cookies and sprinkle with nonpareils.