butter and sugar and beat at medium speed until light and fluffy.
add the eggs, one at a time, and scrape the bottom of the bowl to make sure all the ingredients are well combined.
place the cake flour, baking powder, and salt in a mixing bowl and stir to combine.
combine the milk and vanilla in a measuring cup. alternate adding the milk/vanilla mixture and the dry mixture to the whipped butter/sugar mixture. beat on medium speed for 1½ minutes, scrape the bottom and sides of the bowl, add the remaining milk mixture, and beat for another 30 seconds.
pour the batter into the prepared pan and smooth with a spatula. bake 30-35 