Ultimate Brownies

Ingredients

• 4 (1 ounce) unsweetened chocolate squares
• 1/2 cup butter or 1/2 cup margarine
• 1 cup sugar
• 1 cup firmly packed brown sugar
• 3 eggs, beaten
• 2 teaspoons vanilla
• 1 1/2 cups flour
• 1/2 teaspoon salt
• 1 cup chopped walnuts
• FROSTING
• 2 (1 ounce) unsweetened chocolate squares
• 2 teaspoons butter or 2 teaspoons margarine
• 1/3 cup evaporated milk
• 2 1/2 cups powdered sugar