Scotch Shortbread

Directions

1. 1
   Special Equipment: KitchenAid(R) Stand Mixer; KitchenAid(R) Sifter + Scale Attachment; 8-in/20-cm round cake pan or springform pan; parchment paper
2. 2
   Generously butter the bottom and sides of the cake pan. Line the bottom of the pan with a circle of parchment paper, and butter the parchment. Set aside.
3. 3
   Place the butter in the bowl of your KitchenAid(R) Stand Mixer fitted with the flat beater. Attach the KitchenAid(R) Sifter + Scale Attachment to your mixer. With the ingredient valve closed, weigh the sugar (3.5 oz) in the ingredient hopper. Turn the mixer to medium-low speed, open the ingredient valve, and sift the sugar mixture into the mixing bowl. Cream the butter mixture, on medium speed, until the sugar is incorporated, about 1 minute. Scrape down the bowl once, beat until combined, 30 seconds longer.
4. 4
   Close the ingredient valve. Weigh the flour (12.5 oz) and salt (0.13 oz) in the ingredient hopper, taring the scale between ingredients. With the mixer on low speed, open the ingredient valve, and sift in the flour mixture. Beat on medium speed until the flour is incorporated and the dough turns yellow and starts to bind together, about 1 minute. Stop the mixer once to scrape down the sides of the bowl, and then mix about 30 seconds longer. Remove the mixer bowl, and use a rubber spatula to blend in any flour remaining on the sides of the bowl.
5. 5
   Turn the dough out onto a clean work surface, knead the dough a couple of turns, and then shape it into an 8-in/20-cm round patty that is 1/2-in/12-mm thick. Transfer to the prepared pan, patting it into place, and reshaping it, if needed, to form an even patty without cracks at the edges. Refrigerate for 30 minutes.
6. 6
   Position an oven rack in the center of the oven and preheat the oven to 325°F/160°C/gas 3.
7. 7
   Use the tip of a paring knife to score just the very top of the shortbread, forming 12 even wedges. It is easiest to score the shortbread into quarters and then evenly cut 3 wedges within each quarter section. If desired, prick the surface evenly with a fork, to form a consistent pattern.
8. 8
   Bake until the top of the shortbread is light golden and it begins to pull away from the sides of the pan, 40 to 45 minutes. Cool on a rack for 20 minutes. Run a table knife around the inside edge of the pan to loosen the shortbread. Invert the shortbread over the rack. Peel off the parchment paper, and then turn the shortbread right side up. Let cool completely. Cut into wedges to serve.
9. 9
   OPTIONAL ICING: Stir together 1/4 cup (30 grams) of confectioners' sugar with a tablespoon of milk, lemon juice, brewed coffee, or maple syrup. Wait until the shortbreads are cooled and cut into wedges before drizzling icing over top.