Whisk together the flour, baking powder, baking soda, and salt. Set aside.
Beat butter and powdered sugar together until creamy.
Add the egg, sour cream, vanilla, and almond extract, continuing to beat until combined, scraping the sides of the bowl as needed.
On low speed, add the flour mixture to the butter mixture and stir until combined.
Cover the bowl with plastic wrap and refrigerate for 1 hour.
Preheat oven to 375℉ and line a large baking sheet with parchment paper.
Remove dough from the fridge and divide the dough into 12 equal pieces, rolling each into a ball.
Flatten the dough balls by placing them on a surface lightly dusted with powdered sugar and pressing down on the balls with a flat-bottomed glass dipped in powdered sugar.
Place the flattened cookie dough on the prepared pan, spacing about 2 inches apart.
Bake in preheated oven for 8-10 minutes. The cookies should just be starting to turn golden. Don't overbake. These cookies are meant to be very light in colour.
Transfer immediately to a cooling rack to cool completely.