01 -
Whisk together the all-purpose flour, baking powder, and salt in a medium bowl. Set aside.
02 -
In a large bowl, beat the softened unsalted butter and granulated sugar until light and fluffy. Add the large egg and vanilla extract. Mix until the dough is smooth.
03 -
Divide and color dough if desired. Stack dough layers and roll into a log from the long edge, forming a swirl. Wrap the dough log tightly in plastic wrap and refrigerate for at least 1 hour.
04 -
Preheat oven to 350°F (175°C). Line baking sheets with parchment paper.
05 -
Slice the chilled dough log into 1/4-inch rounds and distribute them on the prepared sheets, spacing each cookie about 2 inches apart.
06 -
Bake at 350°F (175°C) for 10 to 12 minutes until edges are lightly golden. Allow cookies to cool on the sheets for 5 minutes before transferring to a wire rack.