Heat oven to 400°F. Grease cookie sheet. In medium bowl, mix flour, sugar, baking powder and salt. Cut in butter, using fork, until mixture is crumbly. Stir in 2/3 cup milk until dough forms a ball and leaves side of bowl. Stir in additional milk, if necessary, 1 tablespoon at a time, until dough is soft and slightly sticky. Beat 25 strokes.