Put all the dry ingredients into a mixing bowl and mix together thoroughly. Add the rest of the ingredients and beat until well mixed.
Pour the batter into a greased half sheet pan and bake at 350 for 20-25 minutes, or until a wooden toothpick inserted in the center comes out clean.
Cream Cheese Frosting:
Cream the butter with a handheld mixer, then add cream cheese and beat till smooth and then add in the rest of the ingredients and beat until spreading consistency, adding more milk as needed. Spread over the cooled bars.