In large mixing bowl, cream together butter, sugar, and brown sugar for 3-4 minutes or until light and fluffy. Add eggs one at a time, mixing well after each addition. Add vanilla.
Stir in flour, cake flour, cocoa, and salt until mixed together.
Fold in chocolate chips.
Pour into 8 x 8 pan and spread evenly.
Bake for 18-24 minutes.
Let cool.
To make frosting:
Cream butter until light and fluffy. Stir in cocoa, powdered sugar, and cream. Spread on top of cooled brownies.