Remove the gluten-free puff pastry from the refrigerator and allow it to reach room temperature (about 20 to 30 minutes).

On a lightly sugared surface, roll out the gluten-free puff pastry into a rectangle about ⅛ inch thick. Sprinkle granulated sugar to prevent sticking.

Fold each side toward the middle overlapping slightly and then fold again with a ¼ inch gap between layers. Wrap in plastic wrap and refrigerate for 30 to 60 minutes.

Preheat the oven to 400°F (200°C). Slice the chilled dough into ½-inch thick pieces and dip each slice in granulated sugar.

Bake for 20 minutes, flipping each palmier after the first bake, and bake for an additional 10 minutes until golden brown.

Cool completely on a wire rack before serving.