Preheat your oven to 375°F. Line two baking sheets with parchment paper.

Using a hand mixer on medium speed, beat the butter, granulated sugar, and confectioners' sugar together until smooth.

Add the egg and vanilla, mixing until fully incorporated and scraping down the sides of the bowl as needed.

In a separate bowl, whisk together the flour, baking powder, and salt. Gradually add this to the egg mixture, mixing until just combined.

Fold in the chopped pecans until evenly distributed throughout the dough.

Using a 3-tablespoon cookie scoop, place dough balls onto the lined baking sheets, leaving about 2 inches between each cookie.

Press a kitchen glass onto a damp paper towel, then dip it into the additional granulated sugar. Flatten each dough ball to about ½-inch thick using the sugared glass. Repeat for all cookies.

Bake for 9-11 minutes, or until the tops look dry and the edges turn a light golden brown.

Remove from the oven and let the cookies rest on the baking sheets for a few minutes before transferring them to wire racks to cool completely.