2½ teaspoons baking powder
¾ teaspoon salt
16 tablespoons (2 sticks) unsalted butter, softened
1¾ cups sugar
4 large eggs, at room temperature
1 tablespoon vanilla extract
1½ cups whole milk, at room temperature
Beat the butter and sugar together in a large bowl with an electric mixer on medium speed until light and fluffy, 3-6 minutes. Beat in the eggs, one at a time, until incorporated, scraping down the bowl and beaters as needed. Beat in the vanilla.
Reduce speed to low and beat in 1/3 of the flour mixture. Beat in half the milk. Repeat with half of the remaining flour mixture, then the remaining milk, and finally the remaining flour mixture.
Give the batter a final stir using a rubber spatula to make sure it's thoroughly combined. Pour the batter into the prepared pans and smooth the top. Bake until a wooden skewer inserted into the center of the cakes comes out with a few crumbs attached, 25-30 minutes.