Preheat the oven to 325°F. In a small bowl, whisk together the flour, baking powder, and salt. In a large mixing bowl, beat the butter with the sugar. Add the egg and the vanilla extract and mix until light and fluffy. Add half the flour mixture to the butter mixture, beat until combined. Add the remaining flour and beat once more. The mixture should be dry and crumbly, but hold together when you press it between your fingers.
Place a sheet of parchment paper (about the size of a baking tray) on the counter and dump the dough out of the bowl on top of it. Place a second sheet of parchment over the dough. Flatten the dough with your hands and then roll it out to approximately 1/4-inch thickness. Remove the top sheet of parchment and place the parchment on a baking tray. Sprinkle the rolled out dough very generously with about 1/4 cup of Sugar In The Raw. Lightly press the sugar into the dough with your hands or the rolling pin.
Cut into cookies with a circle shaped cutter. Use a thin metal spatula to transfer the cut out cookies to the parchment lined baking sheet, leaving about an inch of space between the cookies. Sprinkle the cookies with the remaining sugar. Bake for 10-12 minutes, or until just barely puffed and not yet brown around the edges.
Let the cookies cool on the pan for 1-2 minutes and then use a metal spatula to transfer the cookies to a wire cooling rack and allow them to cool completely before storing in an airtight container. Enjoy!
Notes
Try not to allow the cookies to brown at all. If they brown, they will still be tasty, but much more crunchy than desired, once they cool. The goal is a very soft shortbread texture.