Fudge Ripple Bars

1 cup butter
2 cups granulated sugar
4 eggs
2 squares unsweetened chocolate, melted
2 teaspoons vanilla extract
1 1/2 cups sifted flour
1 teaspoon baking powder
1 teaspoon salt
1 cup chopped pecans

Cream butter and sugar; add eggs. Blend in chocolate and vanilla extract. Add dry ingredients to creamed mixture and mix well. Stir in pecans and spread in a lightly greased and floured 13 1/2 x 12 1/2-inch pan. Bake at 350 degrees F for 25 to 30 minutes, being careful not to overbake. Cool, then frost.

Frosting
1/3 cup butter
3 cups sifted confectioners' sugar
3 tablespoons cream or milk
1/2 teaspoon vanilla extract
1 square unsweetened chocolate, melted
1 tablespoon melted butter
1 tablespoon confectioners