Preheat your oven to 350°F (180°C) and line your baking sheets with parchment paper or silicone mats.

In a medium-sized bowl, mix together the flour, baking soda, baking powder, and salt. Set this mixture aside.

In a large mixing bowl, beat the unsalted butter, granulated sugar, and light brown sugar together on medium speed until the mixture is light in color and fluffy, about 2-3 minutes.

Crack in the large egg and mix until well combined, then add the vanilla extract and continue mixing until fully incorporated.

Slowly add the dry ingredients to the butter mixture and mix until the dough is well combined without overmixing.

Scoop out cookie dough using 1 ½ tablespoon-sized portions, roll each portion into a ball, and coat it with the additional sugar before placing it on the baking sheet.

Bake the cookies for 7-8 minutes or until just before the edges start to turn golden.

Allow the cookies to cool on the baking sheet for 4-5 minutes before transferring them to a wire rack to cool completely.