CakePreheat oven to 350-degrees.
Grease 9" x 13" cake pan with butter or non-stick spray.
In a large bowl, beat the butter, eggs, and milk.
In another large bowl, combine the flour, cocoa powder, sugar, salt, baking soda, and baking powder. Mix together.
Add the dry ingredients to the wet ingredients and beat until well blended.
Pour into greased pan and cook for approximately 35 minutes, or until a cake tester comes out clean.
Allow to cool.
Frosting
Add the butter to a large bowl and beat until fluffy.
Next, add the powdered sugar and combine (it will still be a little dry).
Now, add the vanilla and half-and-half. Beat until well blended. If the frosting is still a little dry, add more half-and-half (a tsp. at a time). If it's too thin, add a small amount of powdered sugar and mix.
Frost the cake and enjoy!