Preheat oven to 350°F (175°C). Grease and flour a 9-inch (23cm) round springform pan or a regular round cake pan. If using a regular cake pan, line the bottom with parchment paper for easier removal.

In a medium bowl, whisk together the all-purpose flour, baking powder, and salt until well combined. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment (or using a hand mixer), cream the softened unsalted butter and granulated sugar on medium-high speed. Beat until the mixture is light, fluffy, and pale yellow, about 3-5 minutes. Scrape down the sides of the bowl as needed.

Add the large eggs one at a time to the butter mixture, beating well after each addition until fully incorporated. Continue to scrape down the sides of the bowl. Beat in the vanilla extract until just combined.

With the mixer on low speed, gradually add about one-third of the dry ingredients to the butter mixture, mixing until just combined. Pour in half of the whole milk, mixing until just combined. Repeat with another third of the dry ingredients, then the remaining milk, and finally the last third of the dry ingredients. Mix on low speed until the batter is just combined and no streaks of flour remain. Be careful not to overmix, as this can result in a tough cake.

Pour the batter into the prepared cake pan and smooth the top with a rubber spatula. Bake for 50-60 minutes, or until a wooden skewer or toothpick inserted into the center of the cake comes out clean. The top should be golden brown and spring back when lightly touched.

Let the cake cool in the pan on a wire rack for 15-20 minutes. Then, carefully invert the cake onto the wire rack to cool completely. Once completely cooled, dust generously with powdered sugar before slicing and serving.