To the bowl of a stand mixer, add butter and confectioners' sugar. Beat on medium speed until creamy. Add vanilla and orange zest. Mix until incorporated.
In a separate bowl, whisk together flour, cornstarch, and salt.
With the mixer on low, add in flour mixture, one cup at a time.
Gently fold in cranberries.
Add dough to a lightly floured work surface and roll into a 6-inch log, about 3 inches in diameter. Wrap in plastic and seal the ends. Place the dough in the refrigerator to chill for 1 hour, or until firm.
When ready, preheat the oven to 350°F. Line 2 large baking sheets with parchment paper. Remove the dough from the refrigerator and place it onto a cutting board. Slice into ¼-inch cookies and place cookies onto a lined baking sheet about 1 inch apart.
Bake 12-14 minutes, or until lightly browned.
Let the cookies rest for 5 minutes before transferring them to a wire rack to cool.