Preparation

• Make room in your refrigerator for a baking sheet so the shaped cookies can chill for 20-30 minutes. Line two baking sheets with parchment paper or a silicone baking mat.
• In the bowl of a stand mixer fitted with a paddle attachment, cream butter on medium speed until smooth. Slowly add in sugar and salt with the mixer still running on low.
• Add egg yolks, vanilla, and milk while mixing. Continue to mix on medium speed until well combined.
• In a medium-sized mixing bowl, whisk the flour and cake flour. Add flour mixture to mixer in two additions, mixing on low speed until no traces of flour remain.
• Transfer cookie batter to a large piping bag and pipe 2-inch cookies on the prepared baking sheet, spacing them at least 2 inches apart. Chill in the refrigerator for 20-30 minutes.
• Preheat oven to 350°F. Make sure the baking rack is in the middle of the oven.
• Bake for 10-15 minutes or until the edges are lightly golden brown. Let cool on the baking sheet for 5 minutes before transferring to a wire rack.