Preheat the oven to 350 degrees F (175 degrees C). Grease and flour two 8 or 9 inch round cake pans.
In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, mixing well after each addition. Combine the flour, baking powder and salt; stir into the batter alternately with the milk. Stir in vanilla. Distribute batter evenly between the prepared pans.
Bake for 25 to 30 minutes in the preheated oven, until the cake springs back when pressed gently in the center. Cool in pans over a wire rack. When completely cooled, frost or fill as desired.
