Apple Chocolate Brownies

1/2 cup butter or margarine
2 squares unsweetened chocolate
2 eggs
1 cup granulated sugar
1 cup flour
1/2 teaspoon baking powder
1/4 teaspoon salt
1 cup chopped walnuts or pecans
1 cup chopped apple
1 teaspoon vanilla extract

Melt butter and chocolate over low heat. Beat eggs and add sugar. Stir in chocolate mixture and beat well. Stir in dry ingredients, then apples, nuts and vanilla. Bake in a greased 8-inch square pan at 350 degrees F for 25 to 30 minutes. Cool. Dust with confectioners' sugar.