01 -
Combine butter, granulated sugar, and powdered sugar in a mixer and beat well until light and fluffy.
02 -
Add in the eggs, vanilla, and any additional flavoring (if desired), scraping the bottom and sides of the bowl to ensure thorough incorporation.
03 -
Mix in the flour, baking powder, and salt until combined. Divide the dough into three even sized balls.
04 -
Return ⅓ of the dough to the mixing bowl and add 5-10 drops of red gel food coloring, mixing well until the dough is evenly colored. Repeat with another ⅓ of the dough and the green food coloring.
05 -
Flatten each ball of dough into a disc and wrap it in plastic wrap. Chill in the freezer for 20 minutes or in the refrigerator for 1 hour.
06 -
Roll out each disc of dough, one at a time, on a piece of parchment paper to create rectangles of roughly the same size and shape. Stack the thin layers of dough on top of each other with white in the middle and red and green on the top and bottom. Trim the long sides so the edges are even.
07 -
Carefully roll the dough into a tight log, using the bottom piece of parchment paper to lift and roll the dough to avoid cracks. Wrap the dough log in plastic wrap and chill in the refrigerator for at least 1-2 hours.
08 -
Once the dough is chilled, roll in nonpareils on a baking sheet to coat the outside of the log. Press the dough firmly into the sprinkles to ensure good adhesion and coverage.
09 -
Preheat the oven to 350°F and line a baking sheet with parchment paper. Unwrap the roll of cookie dough, cut off the uneven ends, and slice into 1/4-inch cookies using a sharp knife. Place them 1-2 inches apart on the prepared baking sheet.
10 -
Bake for 10-12 minutes until set, then transfer to a wire rack and cool completely before serving.