Using stand mixer fitted with paddle, mix flour, sugar, baking powder and salt on low speed until combined. Add butter, 1 piece at a time, and mix until only pea-size pieces remain, about 1 minute. Add all but 1/2 cup milk mixture, increase speed to medium-high, and beat until light and fluffy, about 1 minute. Reduce speed to medium-low, add remaining 1/2 cup milk mixture, and beat until incorporated, about 30 seconds. Give batter final stir by hand.