Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper.
In a medium bowl, whisk together the all-purpose flour, baking soda, baking powder, and salt. Set aside.
In a large bowl, using an electric mixer, cream the softened unsalted butter and granulated sugar together on medium speed until light and fluffy, about 3-4 minutes.
Add the egg and vanilla extract to the butter-sugar mixture and beat until fully combined.
Gradually add the dry flour mixture to the wet ingredients in three additions, alternating with the whole milk, beginning and ending with the flour mixture. Mix on low speed until just combined and a soft dough forms.
Using a cookie scoop or tablespoon, drop dough balls about 2 inches apart onto the prepared baking sheets.
Bake in the preheated oven for 9-11 minutes, or until the edges are lightly golden but the centers still look soft.
Remove from the oven and allow the cookies to cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.