01 -
Add the butter and sugar to the bowl of a stand mixer. With the paddle attachment, beat at medium speed until creamy, about 3 to 4 minutes. Add egg and vanilla and beat well.
02 -
Whisk together flour, salt, and baking soda. With mixer on low speed, gradually add flour mixture and beat to combine.
03 -
Divide dough into thirds. Color one portion red and one portion green, leaving final third plain. Shape each into a ball, wrap in plastic, and refrigerate for 1 hour.
04 -
Roll each ball between parchment paper into 7-inch squares. Refrigerate for 15 minutes between parchment.
05 -
Stack dough sheets (red, green, plain) and roll into 12x8-inch rectangle. Roll up tightly from long side into log. Wrap in parchment and freeze for one hour.
06 -
Preheat oven to 350 degrees F. Line baking sheets with parchment paper.
07 -
Cut log into 1/3-inch slices with serrated knife. Roll edges in red sanding sugar. Place 1 inch apart on baking sheets.
08 -
Bake for 8-10 minutes until set. Cool on sheet 1 minute before transferring to wire rack.