01 -
In a medium bowl, whisk together flour, baking powder, and salt. In a separate large bowl, cream butter and granulated sugar until light and fluffy. Add the egg and vanilla extract, mixing until incorporated. Gradually add dry ingredients, mixing until a smooth dough forms.
02 -
Divide the dough evenly into two portions. Tint one portion red and the other green using food coloring. Roll each colored dough separately into equal-sized rectangles.
03 -
Layer the green dough rectangle over the red dough rectangle. Starting from the longer edge, tightly roll the layered dough into a log. Gently roll the log in sprinkles to evenly coat the outside. Wrap in plastic wrap and refrigerate for at least 1 hour to firm.
04 -
Preheat oven to 350°F (175°C). Slice the chilled dough log into 1/4-inch thick rounds and arrange on parchment-lined baking sheets. Bake for 10 to 12 minutes, or until edges are just set. Allow cookies to cool completely before serving.