Using a stand mixer with the paddle attachment, cream the butter and vanilla extract together until smooth and fluffy.
Gradually add the powdered sugar and kosher salt, mixing until well incorporated.
Scrape down the sides of the bowl and begin adding the flour in increments of 1/4 cup, continuing to beat on low speed until the mixture forms a cohesive dough.
Transfer the dough to a clean surface, shape it into a rectangle, and wrap it securely in plastic wrap. Chill in the refrigerator for at least one hour, or until firm.
Preheat your oven to 350°F (175°C). Prepare a baking sheet by lining it with parchment paper.
Once the dough is firm, use a sharp knife to slice it into 1/2-inch thick pieces or use a cookie cutter to create desired shapes. Arrange the slices on the prepared baking sheet, ensuring at least an inch of space between each piece.
Bake for approximately 10 minutes, rotating the baking sheet halfway through to ensure even baking. The cookies should be pale with slightly golden edges.
Remove from the oven and carefully transfer the cookies to a wire rack to cool completely.