Position a rack in the center of the oven and heat the oven to 350ºF. Lightly coat two 9x2-inch round cake pans with nonstick cooking spray and line the bottoms with parchment.
Sift the cake flour, sugar, baking powder, and salt into the bowl of a stand mixer fitted with the paddle attachment. Mix on low speed (#2 on a KitchenAid mixer) until the ingredients are well combined.
Add the softened butter pieces and mix on low speed for 20 to 30 seconds to mix the butter into the dry ingredients—the mixture should look a little lumpy, with the largest lumps being about the size of a hazelnut. Add the milk and vanilla extract. Mix on medium speed (#5 on a Kitchen Aid) for 1 min. to thoroughly blend the ingredients and aerate the batter. Scrape the sides of the bowl with a spatula.
Add the eggs one at a time, mixing on medium speed for about 15 seconds after each addition. Scrape down the bowl after the second egg.
Divide the batter equally between the two prepared pans. Use a small offset spatula or spoon to spread the batter evenly in each pan. Bake until the cakes are golden brown and the tops feel firm but spring back a little when tapped lightly with a finger, and a pick inserted in the center of the cake comes out clean, 30 to 35 min. Set the pans on a rack, run a table knife around the edge of each cake and let cool in the pans for 30 min. Invert the cakes onto the rack, lift the pans, peel off the parchment, and let the cakes cool completely before filling and frosting.
Make Ahead Tips
You can bake the cakes up to one day ahead of filling and frosting. Let the cakes cool completely, then wrap them tightly in plastic.
Photo: Scott Phillips