First pre-heat oven to 350 degrees,while the Grease and flour three 6" X 1 1/2" round cake pans.
then Mix together flour, cocoa powder, baking powder and baking soda. Set aside,In a large bowl, beat butter, eggs and vanilla,Gradually add sugar.Beat on medium to high speed for about 3-4 minutes until well mixed.Alternately combine in flour mixture and milk to batter while beating. Continue to beat until batter is smooth.Pour equal amounts of batter into greased pan and floured round cake pans Bake 30 to 35 minutes.Then Check with a toothpick to se if it is done. Bake a few minutes more, if needed.
Remove from oven and allow cakes to cool in pans for a few minutes.Finally Place cakes on a wire rack, to them allow to completely cool.