BUCKINGHAM PALACE SHORTBREAD

Steps:

• 1. In a medium bowl, whisk together the flour, cornstarch and salt until well blended.
• 2. In a stand mixer set on medium speed, beat the butter until creamy. Beat in the granulated sugar until light and fluffy, about 2 minutes, scraping down the sides and bottom of bowl as necessary. On low speed, add the flour mixture in two or three additions until it forms a soft dough.
• 3. Wrap the dough with plastic wrap and chill for 30 minutes.
• 4. Preheat the oven to 350. Line a baking sheet with parchment paper or leave ungreased.
• 5. On a lightly floured surface, roll the dough out to a 3/4 inch thick slab, about 5 X 8 inches. (I used a large frosting spatula to get the edges into shape). Transfer to the baking sheet and bake until lightly golden and firm to the touch, about 40 minutes.
• 6. Slip the parchment paper with the shortbread onto a hard surface. Immediately sprinkle the shortbread heavily with the superfine sugar. While still warm, use the spatula (or other straight, flat tool) and a paring knife, pointed straight down, to cut the shortbread into 1 - 1 1/2 inch pieces. Let cool completely. The shortbread tastes best at room temperature.