01 - Preheat oven to 350°F. Line two baking sheets with parchment paper.
02 - In a medium bowl, whisk together the flour, baking powder, and salt until evenly distributed.
03 - In a large bowl, beat the softened butter and sugar together using an electric mixer until light and fluffy, about 2 to 3 minutes.
04 - Add the egg and vanilla extract to the butter mixture and beat until fully combined.
05 - Gradually mix the dry ingredients into the wet mixture until just incorporated. Do not overmix to keep the cookies tender.
06 - Scoop tablespoon-sized portions of dough and roll into balls. Optionally roll each ball in extra sugar for a sparkly finish.
07 - Place the dough balls 2 inches apart on the prepared baking sheets. Flatten each slightly with the bottom of a glass or the palm of your hand.
08 - Bake for 8 to 10 minutes, until the edges are just golden. Cool on the baking sheet for 2 minutes, then transfer to a wire rack to cool completely.