How to Make It
Heat oven to 325° F.
With an electric mixer, beat the butter and sugar on medium-high speed until light and fluffy, 2 to 3 minutes. Reduce speed to low and gradually add the flour and salt, mixing just until incorporated.
With floured fingers, press the dough into an 8-inch round cake pan. Cut the dough into 12 wedges and prick all over with a toothpick.
Sprinkle the dough with the sanding sugar and bake until golden and firm, 35 to 40 minutes. When cool enough to handle, turn the shortbread out of the pan and use a serrated knife to recut along the lines. Transfer to a wire rack to cool completely. Note: Total Time includes cooling time.