01 -
Combine softened butter and granulated sugar in a stand mixer bowl; beat with paddle attachment at medium speed until creamy, approximately 3 to 4 minutes. Incorporate egg and vanilla extract, mixing thoroughly. Scrape sides of bowl as needed.
02 -
In a separate bowl, whisk together all-purpose flour, kosher salt, and baking soda. Gradually add this flour mixture to the wet ingredients on low mixer speed until fully incorporated. Remove dough and divide evenly into three portions.
03 -
Return one portion of dough to the cleaned mixer bowl, add red gel food coloring, and beat until uniformly colored. Repeat the process with a second portion using green gel food coloring. Leave the third portion uncolored. Form each into a ball, wrap tightly with plastic wrap, and refrigerate for 1 hour.
04 -
Remove dough balls from refrigerator. Place each between parchment paper sheets and roll into 7-inch squares. Chill the rolled dough for 15 minutes, keeping it between parchment to maintain shape.
05 -
Layer the chilled dough squares on a piece of parchment paper in the order of red, green, then plain. Cover with another parchment sheet and roll out gently into a 12 by 8-inch rectangle. Remove the top parchment sheet and, starting from a long edge, roll the dough tightly into a log. Wrap in parchment and freeze for 1 hour to firm.
06 -
Preheat oven to 350°F (175°C). Line two baking sheets with parchment paper and set aside.
07 -
Using a serrated knife, slice the frozen dough log into 1/3-inch thick rounds. Roll edges of each slice in red sanding sugar. Arrange cookies on prepared baking sheets, spacing them one inch apart.
08 -
Bake slices for 8 to 10 minutes until set. Allow cookies to cool on the baking sheet for one minute before transferring to a wire rack to cool completely. Store cooled cookies in an airtight container to preserve freshness.