In a medium bowl, combine the flour, baking powder, and salt; set aside.
In a large bowl with an electric mixer, beat the sugar and 1/2 cup butter until it is creamy. Crack eggs into a dish and add vanilla--DO NOT BEAT. Add the eggs to the butter mixture one at a time and mix for two minutes between each egg. Scrape sides of bowl if necessary.
Slowly add the dry mixture to the running mixer, making sure each addition is well incorporated. Pour batter evenly into two 8-inch greased and floured cake pans.
Bake in a preheated 350º oven for 25 minutes, or until golden brown and cooked through.
Cool for 5 minutes before inverting onto a wire rack; allow to cool for 40 minutes on rack.
PREPARE FROSTING: In a microwave-safe bowl, melt the chocolate, just 10 seconds at a time until just melted. Allow to cool for 10 minutes.
Add the chocolate and butter to a large bowl and beat with electric mixer until it combines. After 2 minutes add the powdered sugar and the milk. When smooth, frost the cake layers and serve immediately.