Preheat oven to 350.F. Grease a tall springform 6-inch round cake pan.
In a bowl mix the flour, baking powder and salt together.
In a mixing bowl cream together the butter & sugar until light and fluffy with a mixer, 3 to 5 min.
Add the egg and vanilla and beat well, scraping down the sides on the bowl.
Now add and beat between each step: 1/3 of the flour mixture, 1/2 the milk, 1/3 of the flour mixture, the remaining milk, and the remaining flour mixture. Scrape down the sides the bowl regularly.
Pour the batter into the prepared pan, and shake it a bit to remove air bubbles. Bake for 30 to 40 minutes, or until a toothpick inserted in the center of the cake comes out clean. Cool for 10 minutes on wire rack before removing from the pan and cool completely before icing.
Ice cake as desired with Swiss Meringue Buttercream