Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans, then line the bottoms with parchment paper rounds.
In a medium bowl, whisk together the sifted all-purpose flour, baking powder, and salt. Set aside.
In a large mixing bowl, beat the softened unsalted butter with an electric mixer on medium speed until creamy, about 1 minute.
Gradually add the granulated sugar to the butter, beating on medium-high speed until light and fluffy, about 3 to 4 minutes.
Add the eggs one at a time, beating well after each addition to fully incorporate.
Mix in the pure vanilla extract until combined.
With the mixer on low speed, alternately add the dry flour mixture and whole milk to the butter mixture, beginning and ending with the flour mixture. Mix just until combined after each addition to avoid overmixing.
Divide the batter evenly between the prepared cake pans and smooth the tops with a spatula.
Bake in the preheated oven for 28 to 32 minutes, or until a toothpick inserted into the center of the cakes comes out clean.
Remove the cakes from the oven and allow them to cool in the pans for 10 minutes.
Run a knife around the edges of the pans to loosen the cakes, then invert them onto wire racks to cool completely before frosting.