Preheat oven to 300 F.

Using an electric mixer, beat until light and well-blended: softened unsalted butter, 1/4 cup powdered sugar, granulated sugar, salt, lemon juice and lemon zest.

Next, sift over the butter mixture: 1 1/6 cups all-purpose flour and 1/3 cup corn starch.

Gradually stir the flour into the butter mixture, then knead until well-incorporated and smooth.

On a floured surface, using a regular rolling pin, roll out the dough into an 8×11-inch rectangle (dough should be about 1/4-inch thick). *If using an embossed rolling pin, at this point, gently roll across the dough to create the design.

Using a 2 1/2-inch round pastry cutter, cut circles in the dough. Place cookies on baking sheet. Continue the process with remaining dough.

Bake for 45 – 50 minutes, or until shortbread is pale gold.

Once cooled, sprinkle with powdered sugar for a slightly sweeter taste.