In either the bowl of a stand mixer or with an electric hand mixer, cream the butter and sugar together for a full 2 minutes. You want this extremely light and fluffy!
Next, scrape sides and add in your egg and vanilla.
Finally, add in your flour and baking powder. The dough will look dry, just keep mixing. Mix, mix, mix and it will come together! The dough should be the same consistency as play-doh. If it is too dry, add some water (1 tsp at a time). If it is too wet, add some flour (1 tsp at a time). This dough is SO forgiving.
Roll and cut your dough into your desired shape and size. Remember, these do not spread, so roll to your desired thickness.
Bake on an ungreased cookie sheet at 350° F until the cookies are no longer wet and glossy on top and have puffed up ever so slightly. The exact timing will depend on how large the cookies are, generally somewhere in the 7-11 minute range.
Allow your cookies to cool and decorate with your favorite frosting. I recommend a crusting vanilla buttercream!
