Line bottom of a 9 x 13 inch baking pan with cooking parchment. Melt chocolate and butter with pepper over low heat. Beat eggs with sugar and vanilla until blended. Stir in cooled chocolate mixture, then kahlua. Resift flour, salt and baking powder into mixture and stir until blended. Add nuts. Turn into pan. Bake in 350 degree oven just until pick inserted in center comes out clean, about 25 minutes (be careful not to overbake). Cook, then spread top with QUICK FUDGE FROSTING. Sprinke with additional nuts, if desired. Cut into squares or bars. *******************QUICK FUDGE FROSTING *********************** Melt 2 squares (1 oz each) unsweetened chocolate and 1 aquare semi-sweet chocolate with 2 tablespoons butter over low heat. Heat 3 tablespoons kahlua and 2 tablespoons heavy cream together. Combine chocolate and kahlua mixtures with 2 cups powdered sugar (free from lumps). Beat until well blended and thick. If necessary, beat in a little extra powdered sugar for good spreading consistency. Frost brownies immediately as mixture stiffens upon setting.