1/2 cup butter
3 (1 ounce) squares unsweetened chocolate
1 cup granulated sugar
2 eggs
1 teaspoon vanilla extract
3/4 cup sifted all-purpose flour
1 1/2 cups chopped walnuts, divided

Combine butter and chocolate in medium-size saucepan. Heat over medium heat, stirring frequently, until melted. Remove from heat. Stir in sugar, using a wooden spoon to mix well. Blend in eggs, one at a time. Add vanilla extract; mix well. Stir in flour and 1 cup of the walnuts. Mix well. Spread batter in a greased 8-inch square baking pan. Bake at 350 degrees F exactly 25 minutes. Do not overbake; brownies should be fudgy. Remove from oven and place pan on wire rack to cool completely. Frost when cooled.

Fudge Frosting
1/2 of a 1 ounce square unsweetened chocolate
1 tablespoon butter
2 tablespoons milk
3/4 cup sifted confectioners' sugar

In a small saucepan over very low heat, combine chocolate, butter and milk. Heat, stirring constantly, until chocolate and butter are melted. Beat in confectioners' sugar. Mix well. Spread frosting on cooled brownies in pan. Sprinkle remaining 1/2 cup chopped walnuts on top. Cut into squares.