Shortbread Cookies

Step 1Preheat the oven to 325°F. Line 2 baking sheets with parchment paper or a silicone baking mat.

Step 2In the bowl of a stand mixer fitted with the paddle attachment, cream the butter and sugar together on medium speed, 2 to 3 minutes. Use a rubber spatula to scrape the sides and bottom of the bowl. Sift in the flour and cornstarch. Mix on low speed until just combined. (If the mixture seems excessively dry, cut in 1 more tablespoon of butter—but only if you really need it.)

Step 3Form the dough into a disc, wrap it in plastic, and refrigerate for 20 minutes.

Step 4On a lightly floured surface, roll the dough out to ¼ - to ⅓-inch thickness. Cut out cookies using a floured 2-inch round cookie cutter. Place on the prepared baking sheets and bake until the edges have the faintest golden tinge (the cookies should not brown), about 20 minutes. Check your oven sooner if it runs hot.