These are classic, buttery, melt-in-your-mouth piped shortbread cookies. The key to the texture is cornstarch and optional milk powder, which adds a richer, toastier flavor. Be aware that the dough is very thick and will be difficult to pipe. This base recipe can be finished in several ways.
Cream butter, powdered sugar, and vanilla until fluffy.
Mix in cream until combined.
Whisk flour, cornstarch, and milk powder separately.
Add dry ingredients to butter mixture and mix on low until just combined.
Preheat oven to 325°F and line baking sheet with parchment.
Transfer dough to piping bag with star tip.
Pipe cookies onto prepared baking sheet.
Bake 10-12 minutes until edges are lightly golden.
Cool on pan briefly before transferring to wire rack.
Notes
Choose one variation if desired. Churro version: Roll warm cookies in cinnamon-sugar. Strawberry version: Dust with strawberry powder. Ribbon version: Add dragees immediately after baking.