Preheat oven to 350ºF, and make sure the rack is in the center of the oven.
Line just the bottom of 2 round cake pans (8" or 9") with parchment paper.
Measure the flour, baking powder and salt into a medium bowl and whisk together or sift together. Set aside.
With an electric mixer cream the butter, then add the sugar and mix on medium speed until pale and fluffy, 3 - 5 minutes. Stop halfway through mixing and scrape down the bowl.
Add the eggs one at time, beating after each addition.
Mix in the vanilla and beat until thoroughly blended.
Reduce speed to low and add the flour mixture and milk alternately in 3 batches; starting and ending with the flour mix.
Mix until batter is just smooth, do not over mix.
Pour batter into the prepared pans and smooth the tops.
Bake for 20 - 25 minutes.
Cake is done when a toothpick or knife inserted into the center comes out clean.
Remove from oven, cool on rack for 7 - 10 minutes, then run a knife around the edge and turn out onto rack to finish cooling. Peel parchment paper off of cake.
Frost when cake is completely cool.