Move oven rack to lower middle position and preheat oven to 350°. Line multiple baking sheets with parchment paper.
Whisk together the flour and baking powder in a bowl and set aside.
Cut butter into cubes. Using a stand mixer fitted with a paddle attachment, beat together until it comes together light and fluffy (approx. 2 minutes or less). Add sugar and continue to beat until incorporated. Do not over beat, you do not want it to get warm. Add the egg and vanilla extract until fully combined.
Switch the mixer speed to low. Gradually add the flour mixture, beating until just combined. Stop the mixer to scrape down the sides as needed. Be careful not to over beat.
Use your hands to work it into a ball for rolling. Roughly divide in half. Turn out on cling wrap. You can use right away or wrap tightly and let rest if you are making this ahead. Can rest for several hours if needed.
Place cling wrap down in rolling space, place unwrapped dough ball on cling wrap, place another layer of cling wrap on top of dough and roll out in between the cling wrap pieces with a wood rolling pin to 1/4″ thick. Once rolled to your liking, remove top layer cling wrap and cut desired shapes. Try not to over handle dough. Place on parchment lined baking sheets.
Place in freezer for 5-10 minutes. Remove and immediately bake for 10-14 minutes, 8-12 minutes for smaller shapes. Ovens may vary so you will need to learn your oven.
Remove from oven and let cool for 2-3 minutes, then transfer to cooling racks.
Let cookies cool completely before decorating. You can store in airtight container for several days at room temperature or freeze to decorate at later date.