In saucepan melt butter. Remove from heat, stir in Cocoa; cool.

In mixing bowl, beat eggs and sugar. Combine flour, baking powder, and salt. Gradually add to egg mixture.

Stir in vanilla and cooled chocolate mixture; mix well.

Spread into greased 13inx9inx2in baking pan. Bake at 350°F for 25-28 mins or until toothpick inserted in center comes out clean, or edges pull away from pan.

Frosting: In mixing bowl cream butter, confectioners sugar, cocoa, and vanilla. Add enough milk until frosting achieves spreading consistency. Spread over cooled brownies.