Add flour, baking powder, and salt to a medium bowl. Whisk to combine. Set aside.
Cream together butter and sugar until light and fluffy, about 3 minutes. Add egg until well-combined. Slowly spoon in flour mixture mixing on medium speed until well-combined, then add vanilla and mix just until combined.
Scoop cookie dough by the tablespoon onto a large baking sheet, leaving about 2-inches between each cookie. Press down on cookie dough ball lightly with the palm of your hand or the bottom of a glass until about 1/2-inch thick. Bake 10-13 minutes until lightly browned.
For the roundest of cookies, you can roll them between your palms before dropping onto the baking sheet. Then, lightly press as directed before baking.
Butter Cookies Recipe https://addapinch.com/butter-cookies-recipe/