A classic cookie that you can make super-duper easy by using store-bought puff pastry.
Preheat the oven to 400 degrees Fahrenheit. Thaw the puff pastry at room temperature for 45 minutes. The dough is ready to use when you can unroll it easily without breaking it.
In a small bowl, combine the sugar and cinnamon.
Place a piece of Gefen Parchment on the counter and sprinkle with some flour. Unroll one of the pastry sheets and place on the parchment with the creases vertical. Roll with a rolling pin to smooth out the creases and to roll out the rectangles about two inches larger on each side.
Sprinkle a quarter of the cinnamon sugar on the dough, covering the entire dough. Place a second piece of parchment on top and use a rolling pin to roll over the dough twice in each direction, pressing the cinnamon sugar into the dough. Place your hand under the parchment and flip it over. Peel off the top piece of parchment and then cover the exposed side of the dough with another quarter of the cinnamon sugar. Return the parchment to the dough and then roll over it with your rolling pin to press the cinnamon sugar into the dough. Remove the parchment from the dough.
Use a dull knife to score (mark, but do not cut completely through) a line horizontally across the middle of the dough. One side at a time, roll tightly from the outside toward the scored line in the middle, using either your fingers or the parchment to help you roll. Stop rolling at the middle line. Repeat with the other side. Fold the sides of parchment up over the rolled dough and place in the freezer. Repeat with the second sheet of dough.
Take the spare piece of parchment you used over the dough and place it on a cookie sheet. Remove the first roll from the freezer and slice it across into three-quarter-inch slices and place cut-side down on the cookie sheet two inches apart. The pastries will appear dry; do not worry about that.
Bake for 14 minutes. Turn the palmiers over and bake for another 5 minutes, watching so they do not burn. Both sides should be equally golden. Slide the parchment off the cookie sheet onto a cooling rack and let the cookies cool at room temperature.
Remove the second roll from the freezer and slice as you did the first roll. Bake as you did the first batch. Store covered with plastic or in an airtight container at room temperature for four days or freeze for up to three months.