Preheat your oven to 350°F (175°C). Grease and flour two 8-inch round cake pans, then line the bottoms with parchment paper.

In a medium bowl, whisk together the sifted all-purpose flour, baking powder, baking soda, and salt. Set aside.

In the bowl of a stand mixer fitted with the paddle attachment, cream the softened unsalted butter and granulated sugar on medium-high speed until light and fluffy, about 3-5 minutes. Scrape down the sides of the bowl as needed.

Add the eggs one at a time, beating well after each addition until fully incorporated. Stir in the pure vanilla extract.

With the mixer on low speed, alternately add the dry ingredients and the buttermilk to the wet ingredients, beginning and ending with the dry ingredients. Mix until just combined and no streaks of flour remain, being careful not to overmix.

Divide the batter evenly between the prepared cake pans. Smooth the tops with a spatula.

Bake for 30-35 minutes, or until a wooden skewer or toothpick inserted into the center comes out clean or with a few moist crumbs.

Remove the cake layers from the oven and let them cool in the pans on a wire rack for 10-15 minutes.

Carefully invert the cake layers onto the wire rack, remove the parchment paper, and let them cool completely before frosting.