Position two oven racks in the middle and upper third of the oven. Preheat the oven to 325 degrees. Line two baking sheets with parchment paper. It is not necessary to butter the paper.

Sift the flour, baking powder, and salt together onto a piece of wax paper or into a medium bowl and set aside.

Put the butter and sugar in a large bowl and beat with an electric mixer on medium speed until the mixture looks smooth and creamy, and the color lightens, about 2 minutes. This thorough beating helps lighten the texture of the cookies. Move the beaters around in the bowl if using a handheld electric mixer. Stop the mixer and scrape dough from the sides of the bowl and any dough that becomes caught in the beaters as needed. Mix in the egg yolk, vanilla, and almond extract until they are blended into the mixture.

Decrease the speed to low and add the flour mixture, mixing just until it is incorporated and a smooth dough forms. At first, the dough forms large crumbs, then it forms a smooth dough that pulls away from the side of the bowl.

Roll 1 level teaspoon of dough between the palms of your hands into _-inch balls. Place the cookie balls 1 1/2 inches apart on the prepared baking sheets.

Bake the cookies for about 20 minutes, reversing the baking sheets after 11 minutes front to back and top to bottom to ensure that the cookies bake evenly. The cookie bottoms and edges will be evenly light brown. Cool the cookies on the baking sheet for 1 minute. Use a metal spatula to transfer the cookies to a wire rack to cool completely.